Just a tip after you drain the fuel rail. Turn the key a few times to pressurize the fuel rail. Then start the engine. Then use a screwdriver to open the Schrader valve in small burst to purge air trapped in the rail. Use a rag to catch the fuel. This will help minimize rough idle.
Perfect video. Everything I have been wondering about fuel injectors answered. The place that does my oil changes wants me to pay a ton of money for some fuel injector cleaning service/product but I'd rather just upgrade them after watching this. (And before I get ripped on for not doing my own oil change... I have severe head injuries so it's no longer worth it to get under my car with the vertigo and migraines it would cause)
Run a can of Techron thru it. ^^ Our stock injectors jump out from under themselves on launch and through the rpm range. 240k miles, 23 mpg, no lift and on stock 225/15's I do not get this mod at all.
For anyone using this video as a guide, please do not use wd40 as a lubricant on your injector seals. Wd40 removes moisture and after a few heat cycles this will cause the o rings to dry out/crack and leak fuel. Use a transmission oil for a lubricant. Transmission oils have conditioners in them to keep seals hydrated and extend the life of the rubber. Pro tip.
@@treychastain4686 Just an old aircraft mechanic and old habit. Current o-ring technology does not use natural rubber. I use Silicone as a general rule = safe for ANY o-rings, then and now. Just shows my age and yours. Any mechanic old enough to have used natural rubbers ones should know this or they were simply imitation mechanics. ;) As you were.
I don't recommend WD40 for "lubricating" anything rubber based. That's not what it's intended for and it WILL dry those o-rings out. Petro gel is the way to go. WD40 does however work great for removing/flushing contaminates and getting bolts unstuck. Definitely would've flushed out that fuel rail with fresh fuel before installing those new injectors though. Other than that, nice vid!
Have you reset the ECU and taken it on a handful of drives so the ECU relearns the new injectors? If so, there could be a possibility of a faulty injector. I would then diagnose with a multi-meter or swap the injectors around and see if other inspector codes pop up to help identity the faulty injector. K Suspension has a lifetime warranty on the injectors. So if you got a bad injector I would contact them and get it replaced.
@@OutJeeping I have reset the ecu and driven it. I had a bad injector on cylinder 6. The code was for injector 6. So Switched it to 1 and it misfires on cylinder 1, so K suspension sent me another one. I installed, reset ecu and drove it around. Now injector 5 is misfiring. I don't get it. 🤷🏻♂️ put my oem ones in and it runs fine no check engine light, no codes.
j'ai commandé des injecteurs pour YJ4 l chez K. Suspension je viens de vérifier la résistance elle est de 12,4 au lieu de 14,5 et ça sur tous les injecteurs, je crois que je vais pas les désinstaller...
For those of you chasing the classic Jeep stumbling issue on cold starts, I’d look to see what your fuel trim is and check your CATs also if not TPS make sure transmission range sensor or neutral safety switch. After you’ve gone through the classic heat soak. Ever since my new engine and fuel injectors it seems like I’m running really rich and just dumping fuel. And when I say every sensor is new it is. No codes.
I installed 4-hole injectors from K Suspension 2 weeks ago. I rarely hear of poor results with these but my XJ ran rough right after and still does with a lot of hesitation upon acceleration almost like a misfire. I’ve given the ECU plenty of run cycles to adjust. 5 of the 6 injectors I replaced were the original Siemens with 360k miles and were working fine. I swapped in hopes of better MPG and better throttle response. I think I’ll go back to what has worked for me for 28 years.
WD actually contains petroleum distillates (paint thinner). WD's main attribute is water displacement. Silicon grease will not only make it easy to install but will remain there for a very long time to help the seals do their job down the road. A nickel's worth of free advice. ^^
I personally use superlube silicone grease but just spraying some WD on the o ring & not soaking them in it won't hurt anything. Most o rings are not natural rubber any how, besides what do you think gas does to them ?
I don't recommend WD40 for "lubricating" anything rubber based. That's not what it's intended for and it WILL dry those o-rings out. Petro gel is the way to go. WD40 does however work great for removing/flushing contaminates and getting bolts unstuck.
In the prior video on how your heat shield works you said the 12 hole injectors should eliminate the heat soak issue. Seemed like you intended to not install the shield after the injector upgrade. Did you just decide to keep it in place or will you be removing it to test the theory?
@@OutJeeping if you wheel the Jeep your gonna have heat soak from the design of your AMC in-line 6 wrapping the exhaust manifold with high heat wrap then making a heat shield for your intake & reinstalling your fuel rail heat shield helps substantially to prevent this from happening….just some things we do with ours from years of experience building trail rigs….these are extremely dependable motors but they get hot & that heats gotta go somewhere if at all possible venting the hood really goes along way but it’s not practical for some so heat shields & good quality heat wrap helps things allot…also worth mentioning a 160 or even a 180 t-stat & flowkooler hi-flo water pump does wonders for keeping the temps down since it doesn’t take much pushing on the gas under load to see temps climb past the typical operating temps if you get stuck in the mud or on a steep hill it’s really easy to overheat a 4slow
I been wanting to get the 4 hole injectors for my 2005 for a while to hopefully boost the mpg a little. While watching your video I ordered mine and am excited to get them. Thanks for the info and the nudge I needed lol.
@@David-rj1ru I installed them just before the cold weather hit so hard to tell about fuel mileage but acceleration is great, no more "flat spots". Although stock ones might have been a little dirty after 63k miles. Hint: use a decent grease on the seals so they don't leak, I used Dielectric grease after 3 leaked lol.
The 4 hole injectors is the best way to go compared to stock injectors, and/or the 12 hole injectors. K Suspension did a video comparison where he took an XJ to a dyno (i6 4.0), he got the HP and Torque results on the first run with the stock injectors, 2nd run was with the 4 hole injectors, 3 run was with the 12 hole injectors. I forget off the top of my head the exact results, but the 4 hole injectors added more Torque and HP over the stock injectors. The 12 hole injectors had a little bit more HP or torque (i forget, it was 1 or the other), but had a considerable amount less HP or torque compared with the 4 hole injectors. I know that may sound confusing, basically the 12 hole injectors had a little more HP, but less Torque, or a little more Torque, but less HP. However, seeing that the vehicle did not have time to "learn" the spefic characteristics of the new sets of injectors (which takes a few complete drive cycles) the test is kind of invalid, in order to see the true HP and Torque numbers, he would have to have a set of injectors installed long enough for the computer to learn the characteristics of each set of injectors, which would fine tune how the vector would control them for optimal performance. However, even with the computer not having time to "learn" the new injectors, its atleast a good baseline to go off of. Also, the 12 hole injectors are more likely to have problems due to the fact that the holes are so small, they get clogged up very easily, which effects the spray pattern, efficiency, and overall performance of the injector, which results in less efficient air/fule atomization, and less efficient burn. When that happens, it leads to carbon buildup, and a host of other problems that come up as it gets worse. Stock injectors are o.k. 4 hole injectors are the best overall 12 hole injectors are just not worth it
Tips for installing new injector: Put then in a container with gasoline before you start disassembling the fuel rail. The gasoline will soften the O rings and they will slide into the fuel rail with no issues.
Did this increase your mpg? Currently my Jeep is running at 11 mpg. Replaced spark plugs, cleaned throttle as well as replaced my TPS and IAC. Kinda hoping this upgrade will increase my mpg.
About to do this job. Just for my sanity, how long did it take before the jeep's PCM fully learned the new injectors? E.g. no more high idle issues etc
If you're still answering questions on this. I have a 98 xj 4.0 auto ! What injector psi lb is correct ? I ordered 19lb 4 hole injectors and lost power due to low psi fuel pressure. Any idea what is correct Lb is ? Most research has conflict
Ok soooo besides the WD40 comment How are the injectors working are you running better than before?? Gas mileage gone up ?? Or down?? Kinda interested in doing this to my TJ however I wanna know how you’re doing first
Haven't had any issues with them yet, no change really in mpg because they are still delivering the same amount of fuel as a single hole injector. But it is a smoother running engine forsure.
is it true the valves are below the injectors and basically blocking the injectors from delivering a clean injection into the cylinder? like the injector is basically blasting petro off the back of the intake valve? if so then wouldn't a single hole injector act as a multi hole hole creating kind of a spray mist effect as the jet stream of fuel OBLITERATES the back of the valve
That is not true for these 4.0 engines. The injectors are on the intake manifold so fuel has time to mix with the air before it is entered into the cylinder.
That’s wasn’t a vacuum hose. That’s a vent hose to the valve cover/crankcase. Check your 4.0 Jeeps. The valve cover hose that goes to the air filter is hollow. The rear valve cover hose has a small hole and goes to the intake manifold. The 4.0 does not have a PCV. If you put 2 small valve/elbows you’ll blow gaskets or seals.
Would my Grand Cherokee 4.0 reset itself if I added both 12 hole injectors and a new 60mm throttle body? Also would you recommend other upgrades as well like coils/ plugs or anything else?
Yup the ecu will learn the new injectors after resetting the computer like shown by disconnecting the battery. The only other ignition coil system that's better than stock would be the Viper Coil mod offered by K Suspension.
I installed 12 hole injectors on my 00 XJ and it leaks gas all along the outside of my header. There’s no sign of leaks from the injectors either. I think I’m getting too much fuel. Could you help me out ?
Would I have to have my 03 Grand Cherokee Laredo stock 4.0 ECM reflashed if I upgrade from stock to the 12 hole? Had different answers a lot so if love a true/ correct answer!!! Thanks for responding!!??
You shouldnt need to reflash the ecu. They are the same pound injectors and the ecu will relearn the new injectors to be able to run efficiently. All that has really changed with the new injectors is fuel spray pattern.
Idk if this question applies to fuel injectors, but I just bought my 98 xj and replaced the tps cause it was giving me a trouble code for it. It seemed to help with the high idle but now my engine will misfire while I’m driving. I’ll be cruising a 2k RPM and it will suddenly drop to below 1k. Wondering if you’ve ever encountered this issue or have any suggestions for a possible fix. I appreciate it
My Jeep did the same exact thing mine is a 95 on a cold start it does exactly what you say but then after it warms up it's fine and smooth but I am burning quite a bit of gas I'm getting 11 to 12 miles a gallon but I have a lot of miles with a lift the gas mileage fluctuates but the injectors were cheap so I'm wondering if they are malfunctioning or not and I'm thinking about going with the four hole
Just normal 89 unless its Thursday at my local station, which 89 is the same price as 87. But there's no reason to change the octane, compression remains the same.
I have installed the injectors into my 97 Cherokee 4.0l, and now the "Check engine" light came on. I reseted the ECU, and strarted a fiew times, but the "Check Engine" light is still on. Idle is rough, too. With the old ones, "Check Engine" Light is off. Anybody has an idea, what to do now?
It takes a few drives for the ecu to learn the new injectors and by resetting it you are making the process start over again. It will run off the factory presets at first till it relearns the new injectors.
you have a bad one possibly. new doesnt always mean good when it comes the china parts especially injectors. i knw this was 5 months ago but what did you do to resolve the issue?
I got that too, with code P0172 system too rich bank 1. Probably bad injector. I got new injectors from Ksuspension and after installing them everything was fien.
I just replaced the factory 1 hole injectors in my 2000 XJ with the 4.0l with the Bosch 12 hole injectors 028015616. Noticed that with them installed and the fuel rail bolted down I can move them 3-4mm up/down its as if they are shorter and did not bottom out (I guess should of compared them before) is this common? It does not leak at all. Thanks
Found out its normal, due to fact that since cannot use the retainer clips that's why...guess if the old ones did not have the clip they would do the same.
@@OutJeeping I watched many clips on installing them and knew about not using the clips but no one mentioned the movement. I sent the company a email and here is what they said " Units move around due the slot for the clips on the injectors being at a different height than the original units. Meaning the injectors can't be locked into the rail like the originals. That's not an issue as long the injectors create a "seal" at the intake so there are no vacuum leaks. Also once the rail is bolted down the injectors have no way of popping out from the rail itself. The fuel pressure alone will always keep the injectors pressed in against the intake ports" Thanks for the reply OutJeeping!
Great video, bud. I haven't gotten my injectors quite yet.. But, I want to know where ya got the custom heat shield. Did you make it yourself, or have a link or company name? Keep up the good work.
Gotta get injectors with equal flow rate or they will increase gas usage. UA-camr nickoftime has a couple of vids on how to find them. I have it in my car and jeep secrets fixes playlist.
@@jethro9341 thanks for the info. I'm thinking that besides getting flow rate correct, one needs to make sure there are no vacuum leaks whatsoever, and for jeeps, a smoke test is a must. Any tiny vacuum leak will force the computer to run richer. My fear of doing this swap is that I will break them!
@@OutJeeping Awesome. I have the original 1 hole. LJ 112,000 miles. I have seen some saying that the 12 hole is running too rich of AFR. I'm up in the air on just going 4 hole or 12. Thoughts?
Did they help with heat soak? I’ve got an 04 WJ and I’ve done hood vents and the E- Fan with a timer set for 5 minutes after running and I’m still getting a heat soak.
Disconnect battery first. Always clean with lacquer thinner wire brush and or sand paper 150 grit lubricate with engine oil . purge your gas by clicking off and on about 8 times. Always let it run 5 minutes on p or neutral then let run on 5 minutes then 5 minutes on drive with choked tires parking brake on idling on park with AC on then while park or neutral then drive each 5 minutes then run it at 40 miles per HR AC off then 40 with AC on the computer should adjust then
@@Taydrum It doesn't matter what you've done to the jeep, it's just going to be better throttle response and smoother running either way. These dont add any more fuel then the stock injectors so therefore the same power.
those heat shields are important. They stop injector from vapor lock. in other words it stops the injectors from overheating and it definitely does happen since jeeps naturally run hot.
@@c.m.229 I have a jeep I worked in a jeep shop, I understand 4.0 vapor lock. Im just saying the home made cover lid thing looks like itd trap more rising heat off the header than it would keep heat out. the factory fix for vapor lock is a heat shield that goes underneath the fuel rail and injectors. if you want a good home made heat shield you wanna put a sheet of metal between the header and intake manifold, theres no heat source that would require a heat shield on top of the intake manifold, that one is basically trapping the heat rising from the exhaust manifold right on top of the injectors and fuel rail.
@@Tanner731 all good I just took it different. I wasnt trying to sound mean or anything else just wanted to make a point about those shields. im not a know it all as i have so much to learn about jeeps even though I have been a jeepster for more than 40 years Im still learning about them and these last few years it is like they change things quicker than they change there underwear also you are right it does look like it .but so many people take them off and wonder why things happen. I apologize!
@@c.m.229 the lid thing hes got going over the fuel rail/injectors isnt stock but he has the stock heat shield in place. Im betting that the home made lid is too hot to touch after driving. the factory heat shield is plenty, if you wanna go overkill DEI makes a really nice looking heat wrap kit for the 4.0 that covers the fuel rail and injectors. my 4.0 has no heat shields and the worst vapor lock it gets is for 2-3 seconds right after restarting while hot on a very hot day and goes away as soon as you blip the gas. thats one advantage to the return style fuel system
I know this is an old video, but just a tip. never use wd-40 or any patroleum based lubricant on o rings. it will break down the rubber over time. you want to use a rubber safe lube. something like silicone spray lube etc.
There has been many studies and opinions on this subject. Bottom line is it won't break down the rubber but it can swell the rubber. For it to swell the rubber it needs to be submerged in WD40 for years on end for that to happen. Using it for a quick spray to install in this video will not affect the rubber. Also from the heat cycles of the engine any residual WD40 most likely has evaporated if there was any left on the O-rings.
Replace the three sensors, on the throttle body. At least one is possibly “failing”. If you want to, try cleaning them after a special soak. UA-cam has videos on this.
@@OutJeeping Glad to hear it! I was considering doing this to my 92, but after yours ran and idled funny I wasn't sure if I would do it. Now it's on the to-do list haha
Come to think of it, does the fuel pump cut on when there's a lack of pressure in the fuel rail like on some newer vehicles? He didn't mention if he disconnected the battery or not
You do realize that "heat sheild" is actually putting your fuel rail in an oven , right? Do yourself a favor and buy a DEI heat wrap for the fuel rail and injectors from KSuspension and do it the right way before you get a problem with vapor locking, FYI.
The heat shield/duct was a project I did back in high school as an alternative way to reduce vapor locking in the fuel rail. I have a bilge fan on a thermo switch that blows air through the fuel rail ducting to dissipate heat.
Yeah same with me but finally got them last round. He sells out with a day or 2 with every batch. Also he has another batch coming in this week so check out his fb page for the notification.
I did installed 12 hole fuel injectors on my xj , it's smoother without a noticeable increase of fuel consumption cruising 100 KPH around 1900 RPM
Just a tip after you drain the fuel rail. Turn the key a few times to pressurize the fuel rail. Then start the engine. Then use a screwdriver to open the Schrader valve in small burst to purge air trapped in the rail. Use a rag to catch the fuel. This will help minimize rough idle.
Perfect video. Everything I have been wondering about fuel injectors answered. The place that does my oil changes wants me to pay a ton of money for some fuel injector cleaning service/product but I'd rather just upgrade them after watching this. (And before I get ripped on for not doing my own oil change... I have severe head injuries so it's no longer worth it to get under my car with the vertigo and migraines it would cause)
Jay S Glad I could help
Run a can of Techron thru it. ^^ Our stock injectors jump out from under themselves on launch and through the rpm range. 240k miles, 23 mpg, no lift and on stock 225/15's
I do not get this mod at all.
Fuck what people think! Do you
I just did the 4 hole injectors in my 01 XJ and they are great so far.
Do you have a part number? Thanks
love the sound of the 4.0L
@Fishermanguy44 lmaoo
@StreetCarz weak ass stomach
For anyone using this video as a guide, please do not use wd40 as a lubricant on your injector seals. Wd40 removes moisture and after a few heat cycles this will cause the o rings to dry out/crack and leak fuel. Use a transmission oil for a lubricant. Transmission oils have conditioners in them to keep seals hydrated and extend the life of the rubber. Pro tip.
Use Vaseline
@@treychastain4686 yeah but most shops/garages have oil laying around not Vaseline lol
Any petroleum based stuff should be avoided on natural rubber. Vaseline is petroleum based and will deteriorate rubber, Trey. ;)
@@AudioFreqx that's odd since every engine builder I know, me included use Vaseline. Have for years and hundreds of motors
@@treychastain4686 Just an old aircraft mechanic and old habit.
Current o-ring technology does not use natural rubber. I use Silicone as a general rule = safe for ANY o-rings, then and now.
Just shows my age and yours. Any mechanic old enough to have used natural rubbers ones should know this or they were simply imitation mechanics. ;)
As you were.
I don't recommend WD40 for "lubricating" anything rubber based. That's not what it's intended for and it WILL dry those o-rings out. Petro gel is the way to go. WD40 does however work great for removing/flushing contaminates and getting bolts unstuck. Definitely would've flushed out that fuel rail with fresh fuel before installing those new injectors though. Other than that, nice vid!
Same thing I was thinking with the liberal amounts of wd 40 everywhere superlube is what I use on rubber O rings
Even Vaseline would be better than wd40
Glad everyone likes the 4 hole and 12 hole injectors. Bought the 4 hole injectors from K suspension and have had nothing but problems
What issue's are you having?
@@OutJeeping misfires, check engine light comes on for injector misfires. I put my original oem fuel injectors back in and it runs fine.
Have you reset the ECU and taken it on a handful of drives so the ECU relearns the new injectors? If so, there could be a possibility of a faulty injector. I would then diagnose with a multi-meter or swap the injectors around and see if other inspector codes pop up to help identity the faulty injector. K Suspension has a lifetime warranty on the injectors. So if you got a bad injector I would contact them and get it replaced.
@@OutJeeping I have reset the ecu and driven it. I had a bad injector on cylinder 6. The code was for injector 6. So Switched it to 1 and it misfires on cylinder 1, so K suspension sent me another one. I installed, reset ecu and drove it around. Now injector 5 is misfiring. I don't get it. 🤷🏻♂️ put my oem ones in and it runs fine no check engine light, no codes.
j'ai commandé des injecteurs pour YJ4 l chez K. Suspension je viens de vérifier la résistance elle est de 12,4 au lieu de 14,5 et ça sur tous les injecteurs, je crois que je vais pas les désinstaller...
For those of you chasing the classic Jeep stumbling issue on cold starts, I’d look to see what your fuel trim is and check your CATs also if not TPS make sure transmission range sensor or neutral safety switch.
After you’ve gone through the classic heat soak.
Ever since my new engine and fuel injectors it seems like I’m running really rich and just dumping fuel.
And when I say every sensor is new it is. No codes.
Your vids are the best! Just installed the 12 hole injectors…. Feels and runs awesome! Thank you for making these vids!
Did you make a review of how it ran after time? Can't find it.
I installed 4-hole injectors from K Suspension 2 weeks ago. I rarely hear of poor results with these but my XJ ran rough right after and still does with a lot of hesitation upon acceleration almost like a misfire. I’ve given the ECU plenty of run cycles to adjust. 5 of the 6 injectors I replaced were the original Siemens with 360k miles and were working fine. I swapped in hopes of better MPG and better throttle response. I think I’ll go back to what has worked for me for 28 years.
Have you just tried replacing your TPS? That sounds like a tps problem to me, with bucking, hesitation and rough idle.
Mine runs great with 4 hole injectors
Just a tip i would check for leaks before you put the heatshield back on
Out J. I'm glad to see you used WD to lubricate the O-rings & NOT PETROLEUM JELLY like most say to use, GOOD JOB.
WD actually contains petroleum distillates (paint thinner). WD's main attribute is water displacement.
Silicon grease will not only make it easy to install but will remain there for a very long time to help the seals do their job down the road.
A nickel's worth of free advice. ^^
I personally use superlube silicone grease but just spraying some WD on the o ring & not soaking them in it won't hurt anything. Most o rings are not natural rubber any how, besides what do you think gas does to them ?
I don't recommend WD40 for "lubricating" anything rubber based. That's not what it's intended for and it WILL dry those o-rings out. Petro gel is the way to go. WD40 does however work great for removing/flushing contaminates and getting bolts unstuck.
Were is the second video i would like to see how many mpg before and after
In the prior video on how your heat shield works you said the 12 hole injectors should eliminate the heat soak issue. Seemed like you intended to not install the shield after the injector upgrade. Did you just decide to keep it in place or will you be removing it to test the theory?
Eugene Williams I've had it off for a couple months and haven't had heat soak yet.
Tin foil wraps ^^
The injectors have nothing to do with heat soak that’s a flaw in the design of a amc in-line 6…heat rises and the exhaust manifold is below the intake which is what allows the exhausts temps to heat your intake air temps up and again heat up your injectors & fuel temps so heat shielding is a must for any in-line 6 Jeep that’s going to be used off road or in harsh conditions….anyone mall crawling the sheetz parking lot 🤣 will never experience any issues with heat soak though it sounds cool when they’re comparing who has the “most modded yeep” ©
@@OutJeeping if you wheel the Jeep your gonna have heat soak from the design of your AMC in-line 6 wrapping the exhaust manifold with high heat wrap then making a heat shield for your intake & reinstalling your fuel rail heat shield helps substantially to prevent this from happening….just some things we do with ours from years of experience building trail rigs….these are extremely dependable motors but they get hot & that heats gotta go somewhere if at all possible venting the hood really goes along way but it’s not practical for some so heat shields & good quality heat wrap helps things allot…also worth mentioning a 160 or even a 180 t-stat & flowkooler hi-flo water pump does wonders for keeping the temps down since it doesn’t take much pushing on the gas under load to see temps climb past the typical operating temps if you get stuck in the mud or on a steep hill it’s really easy to overheat a 4slow
I been wanting to get the 4 hole injectors for my 2005 for a while to hopefully boost the mpg a little. While watching your video I ordered mine and am excited to get them. Thanks for the info and the nudge I needed lol.
Did you get the 4 hole injectors or the 12 hole injectors like in the video?
@@DustySteel 4 hole
How are they?
@@David-rj1ru I installed them just before the cold weather hit so hard to tell about fuel mileage but acceleration is great, no more "flat spots". Although stock ones might have been a little dirty after 63k miles. Hint: use a decent grease on the seals so they don't leak, I used Dielectric grease after 3 leaked lol.
@@YobieTheQuestioner heard
I've been looking for the follow up video. in the end would you recommend these over a 4 hole injector?
The 4 hole injectors is the best way to go compared to stock injectors, and/or the 12 hole injectors. K Suspension did a video comparison where he took an XJ to a dyno (i6 4.0), he got the HP and Torque results on the first run with the stock injectors, 2nd run was with the 4 hole injectors, 3 run was with the 12 hole injectors.
I forget off the top of my head the exact results, but the 4 hole injectors added more Torque and HP over the stock injectors.
The 12 hole injectors had a little bit more HP or torque (i forget, it was 1 or the other), but had a considerable amount less HP or torque compared with the 4 hole injectors.
I know that may sound confusing, basically the 12 hole injectors had a little more HP, but less Torque, or a little more Torque, but less HP.
However, seeing that the vehicle did not have time to "learn" the spefic characteristics of the new sets of injectors (which takes a few complete drive cycles) the test is kind of invalid, in order to see the true HP and Torque numbers, he would have to have a set of injectors installed long enough for the computer to learn the characteristics of each set of injectors, which would fine tune how the vector would control them for optimal performance. However, even with the computer not having time to "learn" the new injectors, its atleast a good baseline to go off of.
Also, the 12 hole injectors are more likely to have problems due to the fact that the holes are so small, they get clogged up very easily, which effects the spray pattern, efficiency, and overall performance of the injector, which results in less efficient air/fule atomization, and less efficient burn. When that happens, it leads to carbon buildup, and a host of other problems that come up as it gets worse.
Stock injectors are o.k.
4 hole injectors are the best overall
12 hole injectors are just not worth it
@@p.j.vallier9197 Wow nice post!
Tips for installing new injector:
Put then in a container with gasoline before you start disassembling the fuel rail. The gasoline will soften the O rings and they will slide into the fuel rail with no issues.
Interesting, Thanks
@@OutJeeping So did this eventually work?
@@David-rj1ru Havent tried it with gasoline
@@OutJeeping wait what? I wanna injector but I need more info. I have seen guys do it without unplugging ecu
@@David-rj1ru www.ksuspensionfab.com
If i bought these for a 92 jeep cherokee 4.0 I6 i need pigtails?
Yes, your harness would be for the older injectors so you would need the pigtail adapters.
Thank you for this channel. Helps a lot.
Did this increase your mpg? Currently my Jeep is running at 11 mpg. Replaced spark plugs, cleaned throttle as well as replaced my TPS and IAC. Kinda hoping this upgrade will increase my mpg.
I didn't notice in increase in mpg but have noticed an overall smoother running engine with increase throttle response.
About to do this job.
Just for my sanity, how long did it take before the jeep's PCM fully learned the new injectors? E.g. no more high idle issues etc
After 5-6 or so trips, it got better as I continued to drive it.
If you're still answering questions on this. I have a 98 xj 4.0 auto ! What injector psi lb is correct ? I ordered 19lb 4 hole injectors and lost power due to low psi fuel pressure. Any idea what is correct Lb is ? Most research has conflict
this is 6 years ago... this is now 2024 and are you still on the same 12 hole injector today?
I sold the jeep 4 years ago, so I don't know. But they were still good when I sold it.
Ok soooo besides the WD40 comment
How are the injectors working are you running better than before??
Gas mileage gone up ??
Or down??
Kinda interested in doing this to my TJ
however I wanna know how you’re doing first
Haven't had any issues with them yet, no change really in mpg because they are still delivering the same amount of fuel as a single hole injector. But it is a smoother running engine forsure.
My experience when using WD40 on o-rings is that it dries out the o-ring. Have you had to replace the o-rings since you installed the injectors?
Nope, haven't had any issues
@@OutJeeping 👍
is it true the valves are below the injectors and basically blocking the injectors from delivering a clean injection into the cylinder? like the injector is basically blasting petro off the back of the intake valve? if so then wouldn't a single hole injector act as a multi hole hole creating kind of a spray mist effect as the jet stream of fuel OBLITERATES the back of the valve
That is not true for these 4.0 engines. The injectors are on the intake manifold so fuel has time to mix with the air before it is entered into the cylinder.
That’s wasn’t a vacuum hose. That’s a vent hose to the valve cover/crankcase. Check your 4.0 Jeeps. The valve cover hose that goes to the air filter is hollow. The rear valve cover hose has a small hole and goes to the intake manifold. The 4.0 does not have a PCV. If you put 2 small valve/elbows you’ll blow gaskets or seals.
When swapping injectors always use some grease on the o rings or installation
Would my Grand Cherokee 4.0 reset itself if I added both 12 hole injectors and a new 60mm throttle body? Also would you recommend other upgrades as well like coils/ plugs or anything else?
Yup the ecu will learn the new injectors after resetting the computer like shown by disconnecting the battery. The only other ignition coil system that's better than stock would be the Viper Coil mod offered by K Suspension.
Great video as always. How are they holding up?
Haven't had an issue yet
I installed 12 hole injectors on my 00 XJ and it leaks gas all along the outside of my header. There’s no sign of leaks from the injectors either. I think I’m getting too much fuel. Could you help me out ?
Are you saying its leaking on the exhaust header or intake manifold where the injector goes into? It could possibly be a faulty stuck open injector.
Would I have to have my 03 Grand Cherokee Laredo stock 4.0 ECM reflashed if I upgrade from stock to the 12 hole? Had different answers a lot so if love a true/ correct answer!!! Thanks for responding!!??
You shouldnt need to reflash the ecu. They are the same pound injectors and the ecu will relearn the new injectors to be able to run efficiently. All that has really changed with the new injectors is fuel spray pattern.
Idk if this question applies to fuel injectors, but I just bought my 98 xj and replaced the tps cause it was giving me a trouble code for it. It seemed to help with the high idle but now my engine will misfire while I’m driving. I’ll be cruising a 2k RPM and it will suddenly drop to below 1k. Wondering if you’ve ever encountered this issue or have any suggestions for a possible fix. I appreciate it
I would definitely look over the fuel injectors and the whole ignition system and replace any worn out components.
Now that you've had them in for a while, has the jeep been running better after the ecu relearned them?
For some reason it runs choppy on cold starts as if the motor is cammed, don't know why its doing that but other than that it runs fine.
My Jeep did the same exact thing mine is a 95 on a cold start it does exactly what you say but then after it warms up it's fine and smooth but I am burning quite a bit of gas I'm getting 11 to 12 miles a gallon but I have a lot of miles with a lift the gas mileage fluctuates but the injectors were cheap so I'm wondering if they are malfunctioning or not and I'm thinking about going with the four hole
Beautiful XJ great video!
What are you using for your exhaust in your XJ...sounds nice!
Flowmaster Super 44
@@OutJeeping
Thanks for letting me know that...
What is that you have wired to your fuel rail?? some kind of thermal sensor?
Thermal switch that kicks on around 135 degrees I believe.
I got my injectors out of an 07 chevy hhr so far I dont know if it is mental or not but i feel the improvement
5 years ago, did it help with the mpg?
Not really but I knew that going into it
You guys still run regular 87 octane or 89 octane in your cherokees after the 12 hole swap?
Just normal 89 unless its Thursday at my local station, which 89 is the same price as 87. But there's no reason to change the octane, compression remains the same.
For some reason I burn more fuel with these injectors I normally get 450km to 480km on full tank and now hit half of that any suggestions?
How long have you had them installed for? It takes some time for the computer to relearn the new injectors.
How long did it take for the jeep to run properly after the install?
It seemed after about 10 drives it seem to start to learn the new injectors and smoothen out
@@OutJeeping yeah I heard it takes a while. Thanks for the heads up.. You notice anything performance wise? Economy wise?
oh my god dude that thing sounds sick nice
I have installed the injectors into my 97 Cherokee 4.0l, and now the "Check engine" light came on. I reseted the ECU, and strarted a fiew times, but the "Check Engine" light is still on. Idle is rough, too. With the old ones, "Check Engine" Light is off. Anybody has an idea, what to do now?
It takes a few drives for the ecu to learn the new injectors and by resetting it you are making the process start over again. It will run off the factory presets at first till it relearns the new injectors.
you have a bad one possibly. new doesnt always mean good when it comes the china parts especially injectors. i knw this was 5 months ago but what did you do to resolve the issue?
I got that too, with code P0172 system too rich bank 1. Probably bad injector. I got new injectors from Ksuspension and after installing them everything was fien.
any update on the injectors? interested in buying wondering how they've held up. thanks!
Seem to be working great no problems yet
I just replaced the factory 1 hole injectors in my 2000 XJ with the 4.0l with the Bosch 12 hole injectors 028015616. Noticed that with them installed and the fuel rail bolted down I can move them 3-4mm up/down its as if they are shorter and did not bottom out (I guess should of compared them before) is this common? It does not leak at all. Thanks
Found out its normal, due to fact that since cannot use the retainer clips that's why...guess if the old ones did not have the clip they would do the same.
@@recountry Yup I dont think I was able to reuse the clips on mine either.
@@OutJeeping I watched many clips on installing them and knew about not using the clips but no one mentioned the movement. I sent the company a email and here is what they said " Units move around due the slot for the clips on the injectors being at a different height than the original units. Meaning the injectors can't be locked into the rail like the originals. That's not an issue as long the injectors create a "seal" at the intake so there are no vacuum leaks. Also once the rail is bolted down the injectors have no way of popping out from the rail itself. The fuel pressure alone will always keep the injectors pressed in against the intake ports" Thanks for the reply OutJeeping!
What do you call the thing at the top of your windshield? Just got my first xj and this is one of the first mods I wanna do.
That would be a visor, they are pretty rare for Cherokees
How did the 12 hole injectors work out? Still running them?
I never had an issue with them till I sold the Jeep last summer. I plan to run them on my current Jeep as well.
Great video, bud. I haven't gotten my injectors quite yet.. But, I want to know where ya got the custom heat shield. Did you make it yourself, or have a link or company name? Keep up the good work.
I explain it all in this video: ua-cam.com/video/TdRiohWjfIA/v-deo.html
Thanks!
I did the 4 hole injector swap and the only increase I noticed was how much more gas I'm buying. Those things destroyed my mileage.
Gotta get injectors with equal flow rate or they will increase gas usage. UA-camr nickoftime has a couple of vids on how to find them. I have it in my car and jeep secrets fixes playlist.
You must mean NickInTimeFilms? Yeah I follow him. I still got shitty mileage. This 'upgrade' is not all its cracked up to be.
@@jethro9341 thanks for the info. I'm thinking that besides getting flow rate correct, one needs to make sure there are no vacuum leaks whatsoever, and for jeeps, a smoke test is a must. Any tiny vacuum leak will force the computer to run richer. My fear of doing this swap is that I will break them!
Also pay attention, 98 and older you will have to splice the wires if you chose the Pig tail version. The adapter ones have a high fail rate
good to know!
So did the 12 hole injectors ever smooth out? Are you still running them>
Yup they smooth out after a few drives and still running them after after a couple years of them installed.
@@OutJeeping Awesome. I have the original 1 hole. LJ 112,000 miles. I have seen some saying that the 12 hole is running too rich of AFR. I'm up in the air on just going 4 hole or 12. Thoughts?
Did they help with heat soak? I’ve got an 04 WJ and I’ve done hood vents and the E- Fan with a timer set for 5 minutes after running and I’m still getting a heat soak.
does this add power?acceleration?
It has in increase in throttle response and atomizes the fuel better which helps for smoother running.
Disconnect battery first. Always clean with lacquer thinner wire brush and or sand paper 150 grit lubricate with engine oil . purge your gas by clicking off and on about 8 times. Always let it run 5 minutes on p or neutral then let run on 5 minutes then 5 minutes on drive with choked tires parking brake on idling on park with AC on then while park or neutral then drive each 5 minutes then run it at 40 miles per HR AC off then 40 with AC on the computer should adjust then
How is the fuel economy after installing the new 12 hole fuel injectors ,any improvements?
Around the same
@@OutJeeping I would not expect any real difference if you have a lift kit, mud tires, and wider tires
@@Taydrum It doesn't matter what you've done to the jeep, it's just going to be better throttle response and smoother running either way. These dont add any more fuel then the stock injectors so therefore the same power.
@@OutJeeping Ah I didn't realize they add the same amount of fuel.
Stock injectors are 19lb the 12 hole ones are 24lb
How does heat shielding work above the fuel rail
It was a engineering project I was working on at the time. I have it all explained in this video ua-cam.com/video/TdRiohWjfIA/v-deo.html
that top part of the heat shield looks like it would trap heat from the header not be a barrier for heat coming from the header
those heat shields are important. They stop injector from vapor lock. in other words it stops the injectors from overheating and it definitely does happen since jeeps naturally run hot.
@@c.m.229 I have a jeep I worked in a jeep shop, I understand 4.0 vapor lock. Im just saying the home made cover lid thing looks like itd trap more rising heat off the header than it would keep heat out. the factory fix for vapor lock is a heat shield that goes underneath the fuel rail and injectors. if you want a good home made heat shield you wanna put a sheet of metal between the header and intake manifold, theres no heat source that would require a heat shield on top of the intake manifold, that one is basically trapping the heat rising from the exhaust manifold right on top of the injectors and fuel rail.
@@Tanner731 all good I just took it different. I wasnt trying to sound mean or anything else just wanted to make a point about those shields. im not a know it all as i have so much to learn about jeeps even though I have been a jeepster for more than 40 years Im still learning about them and these last few years it is like they change things quicker than they change there underwear also you are right it does look like it .but so many people take them off and wonder why things happen. I apologize!
@@c.m.229 the lid thing hes got going over the fuel rail/injectors isnt stock but he has the stock heat shield in place. Im betting that the home made lid is too hot to touch after driving. the factory heat shield is plenty, if you wanna go overkill DEI makes a really nice looking heat wrap kit for the 4.0 that covers the fuel rail and injectors. my 4.0 has no heat shields and the worst vapor lock it gets is for 2-3 seconds right after restarting while hot on a very hot day and goes away as soon as you blip the gas. thats one advantage to the return style fuel system
How is the mpg?
About the same
I know this is an old video, but just a tip. never use wd-40 or any patroleum based lubricant on o rings. it will break down the rubber over time. you want to use a rubber safe lube. something like silicone spray lube etc.
There has been many studies and opinions on this subject. Bottom line is it won't break down the rubber but it can swell the rubber. For it to swell the rubber it needs to be submerged in WD40 for years on end for that to happen. Using it for a quick spray to install in this video will not affect the rubber. Also from the heat cycles of the engine any residual WD40 most likely has evaporated if there was any left on the O-rings.
Petroleum jelly is petroleum as where gasoline comes from. don't think it'll harm O-rings. WD-40 is a lubricating solvent.
What pound injectors are these
240cc Flow Rate
Would you recommend these over 4-hole instead? If so why?
steven padilla
The 4 holes are just fine but the 12 hole atomises a bit better and usually they’re 24/lbs an hour vs the stock 19/lbs
Nampa, ID... well I might just walk on over.
I would be worried about not using those clips.You should make yourself some new battery cables and put on some military style connectors....
Did you make a follow-up video?
I did not unfortunately, but they were working well after 2 years.
@@OutJeeping did you see an improvement in gas mileage?
I did the K Suspension 4 hole remains a little over a month ago and at idle it won’t go below 1000rpms any ideas how to fix it
Usually the computer will learn the new injectors after a couple days of driving, are you sure you didn't create a vacuum leak when installing them?
OutJeeping not sure I’ll have to look into that thank you
Replace the three sensors, on the throttle body. At least one is possibly “failing”. If you want to, try cleaning them after a special soak. UA-cam has videos on this.
Great video good job
Did you ever do a review/update video on these?
I did not, but after a couple of years I can say they are still working flawlessly.
@@OutJeeping Glad to hear it! I was considering doing this to my 92, but after yours ran and idled funny I wasn't sure if I would do it. Now it's on the to-do list haha
How do you like the new injectors?
Work just fine, smooth running and better throttle response
Any improvement with your mpg?
Nothing noticeable, but better throttle response.
Isn’t the right link. Where can I buy these?
Link seems to be working fine to their website, under their products tab you can find injectors that fit to your application.
Where do you get the decals on the fender?
I got mine off of Ebay, I forget the sellers name but they are stencil style decals.
What’s type of exhaust do you have
Flowmaster Super 44
What exaust do you have man? It sounds great!
Flowmaster super 44 no cat.
Do u know the Bosch part number?
I do not
Will it add horse and help fuel eco?
Nothing noticeable its mostly for smoother running and throttle response.
Are the 12 hole plug n play for a 99 jeep xj?
They are for the 99-01 Cherokee XJ's
quality video
Thanks
Any update on this video
All I can say is they are doing well with no complaints so far and throttle response has improved over stock.
No adjustments of timing were needed?
Juan Luis Nope, it doesn't change the amount of fuel going into the engine.
Will it pass smog??
It should certainly, doesnt tamper with any of the exhaust.
Don’t take off the fuel rail with a hot engine ...don’t ask why but let just say it got a little toasty
Come to think of it, does the fuel pump cut on when there's a lack of pressure in the fuel rail like on some newer vehicles?
He didn't mention if he disconnected the battery or not
Only when the key is turned it will prime before cranking, and then run continuously when the engine is running.
You do realize that "heat sheild" is actually putting your fuel rail in an oven , right? Do yourself a favor and buy a DEI heat wrap for the fuel rail and injectors from KSuspension and do it the right way before you get a problem with vapor locking, FYI.
The heat shield/duct was a project I did back in high school as an alternative way to reduce vapor locking in the fuel rail. I have a bilge fan on a thermo switch that blows air through the fuel rail ducting to dissipate heat.
Would this work on a 93 zj 4.0?
Yes, you may need to get the wire harness adapters though.
Mine is running stupid rich now what do
Have you rest the ecu and driven it a few times?
@@OutJeeping yup did it all got 4 port ones and she ran fine
What’s ur exhaust set up
Flowmaster super 44 no cats
OutJeeping sorry , but from where did you but it ?
Should have painted the fule rail while it was out
No better performance than Bosch 4 hole injectors.
$175 for reman at K suspension now
How much are the pig tails or what ever you called en
Check out the link in the description
WD40, not on electric connection! Please
I used wd40 on the o-rings as lube not on the electrical connector
Dude a set of these are 900 bucks. The point of a Jeep is it's fun and a good vehicle to work on. Good vid but wow
Hmm, not sure where you got that price from but on the K Suspension website they are $150 for 12 hole reman injectors.
@@OutJeeping you are correct sir I saw an incorrect figure. Thx. ......see UA-cam I was wrong and apologized and all is well....
50 times or 150 miles. Whichever comes first.
hi you forgot to turn on the caption caption please thank you like you'r channel I watch you on UA-cam C😎😎L
Just added captions.
OutJeeping thank you for adding caption will watch now that I can under stand what you'r saying 👍👍👍 C😎😎L
I just wish these were in stock. Ive been checking in weekly for the past three months and they're always out of stock
Yeah same with me but finally got them last round. He sells out with a day or 2 with every batch. Also he has another batch coming in this week so check out his fb page for the notification.
Search eBay for jeep 12 hole injector upgrade
Just so you guys know eBay has the 12 hole Bosch reman for 80$ with free shipping
These are just stock 2007 Ford Focus 2.0 injectors. The Bosch number is 0280156161.
WD 40 is bad for use on rubber not a good idea
Gasoline is bad for rubber too. The seals are Viton or something similar.
This was a waste of money for me jeep ran way too Rich no matter what I did failed smog, went back to stock 1hole and passed
Where's that review video at???
Haven't got to it yet but theres not much to say, they're still working great