This is by far the best explanation of EGR functions and diagnostic steps on UA-cam. Helped me a great deal in troubleshooting my son's 1994 Tacoma. Can't thank you enough!
You taught me the difference between the TVV, and the VSV, and that these are always located between the EGR and the vacuum modulator. I learn something new everyday.
You are a gentleman and a scholar. I failed smog on my 1997 Toyota Tacoma, first time I had to replace the distributor cap and rotor, spark plugs and wires, but then I blew NO so much I was a gross polluter. I had no idea what to do, I replaced the air filter and cleaned the MAF sensor, still failed. Coming to this video, I bought a vacuum tool much like yours (not the cheap looking one, avoid), and it was my EGR valve that was stuck, like very dirty stuck, which I discovered when I tried to stall the engine by sucking on the ERG port. Long story short, I pull the EGR valve, cleaned it with carburetor cleaner, checked everything else per your video, and took it in for the 5th smog test, and it passed. Without your video I would have been lost. You are without a doubt a golden nugget of the internet, superb hands-on explanation.
Dudde, you are absolutely awesome! I spend days trying to learn about how the EGR and vacuum works, ...so confusing, but in 20 minutes I learn from you a lot. Thanks for taking the time. Now im gonna try to fix the 71 code on my 91 Toyota 22re.
This was and is a fantastic troubleshooting video. This helped me so much today working on a slow starting 1992 4Runner. I diagnosed, well you diagnosed, that my EGR was stuck closed. What I found was yes that was true, but also the back pressure port from the EGR to the modulator was clogged almost 100%. The hose also was nasty. Now I say that because I got vacuum off the back of the modulator and thought is was good. But still this video brought me to the problems, so Thank You!!!
I was impressed at the image quality and sound quality. You were easy to understand and follow! Thanks a ton for this video would love to see more videos on these toyotas!
Thanks for the detailed lesson on EGR systems. I was wondering how it all worked and now that I know it's just that much easier to deal with the mess of vacuum hoses under the hood. One thing that helps too is just labeling the hoses and wires, I did mine with matching numbers at hose and connector, it took more time but in the end it will save time and headaches. This is my first rebuild and I had hoped just the top end needed work but unfortunately once I pulled the head off I diagnosed a rod knock in cylinder 2 as well so now I get to pull my first complete engine. I noticed in the process that my EGR valve was fossilized inside so it's why I searched ... I'm glad I stumbled onto your video. Great stuff! 🙏
WOW... thanks to your video, after a year and a half of trying to figure out why my pickup was throwing a code 71 and a lot of $ spent, I found out the shop that put a new head gasket in. Put the throttle body gasket on backwards, whichh gave a vacuum leak.
Excellent vid. I have a 91 4x4 pickup with the same engine and for the first time ever, it failed tucson, az. emissions. I will check the egr system this morning. Thank technology for you tube and people like you for these videos
Great video! Fixed the egr system on a 98 Camry recently and I wish I had known about this video! Ended up parts cannoning it and replacing all 3 components. It worked, the parts were cheap and there was no way I could figure out how that crazy system works and diagnose it properly. Now I know!
Great video. It helped me check out my system on my 91 pick up. Everything tested good but I was still getting a check engine lite. When I put vacuum to the egr valve it would hold vacuum but it wouldn't die barely a stumble. I removed egr valve cleaned out and tested. Tested good and reinstalled. Still had a lite and no die. I found out the clog was in the plenum. I removed the plenum and cleaned out the passage. It runs the length of the plenum and the other end of the passage is right behind the throttle body inside the plenum. Runs great, no lite, and dies whenever vacuum is applied to egr. Thanks for all the info.
Eight seconds in, you said, "It has some EGR problems." Like what ? Failed smog ? Rough idle ? Peeling paint ? Thanks. The video itself is really well made. Good sound, lighting, script, demonstrations. Thanks again.
Thanks for responding. I got this goofy 1994 4 runner which passed smog but I Just realized that there IS NO PCV VALVE. Just a hose ! So I just added one. And there is no vacuum going to EGR modulator. I suspect the seller and smog test tech had a deal going. yikes
Just checked ... "P, E and R" vacuum ports on top of throttle body have NO vacuum, Even tho the other one right there does. I love a good mystery. Thanks again for your videos. Without it I would just take it to the shop. Boring.
Blow them out, clean out the passages with a fine steel wire like the strand from a bicycle brake cable. Blow them out with compressed air. You'll get your passes back. Then make sure your vacuum lines ain't clogged.
Wow! Outstanding video. Thank you so much for the clear explanation. I could have watched 100 other videos and not learned what I did from this one. Very well done. Excellent presentation. Thank you!
Man you are the Man! Im trying to learn as much as i can about my 94 4wd pickup with the 22re; and u have explained the egr more effectively than anyone thus far... im gonna check ur other vids. thanks!
NICE, It definitely helps me out! Thanks a lot for sharing. I'm trying to understand how the EGR works or not work.I have a California emissions 1986 and it has the temp-controlled VSV shown at 6:25. Toyota actually calls it the "Bimetallic Vacuum Switching Valve", hence VSV nomenclature on vacuum diagram.
Thanks 👍. On a trip atm and I had to stop for roadworks. Car idled very poorly, and when I drove off had no power with knocking. Stopped the engine and all came good when restarted Thanks to you I'll be able to find the culprit when home ...Cheers ! PS Toyota Avalon with vacumn EGR.
Very excellent video. My 92 Toyota pickup with 22RE looks exactly like the EGR system in the video. I am still not clear on which vacuum line is which for P and R that starts at the throttle body. Anyway, this video helps me out a bunch. Next time I change head gasket or what ever all those vacuum lines are going bye bye.
Thanks. Thats a great video. Easy to follow and you did a really good job. i wish you did alot of videos on other things that are wrong with cars, trucks ect.
The first thing to check when a P-0401 pops up is hoses - cracks defeat vacuum modulation. Second is the modulator: at some point [with age] the diaphragm of this will crack. You will get the code, and mileage will drop noticeably. With no dilution of intake air by exhaust gases, your O2 sensors will detect a lean condition, and long term fuel trim goes way up to compensate - its doubly worse than simple vacuum leaks on a system where EGR contol is working properly. If the above fails, solenoid valves may be the culprit - they may be a normally open or a normally closed design depending on engine Having experienced the fullness of this fault, its depressing: a small, low power v6 engine... getting big block ford kind of mileage of 8-11mpg. New modulator brought back 16/21 mielage like it had when brand new.
Had nothing but problems with my 3vze engine 1993 T100 with high NOx smog etc, the EGR valve is opening, completely clear, replaced the EGR modulator with new valve OEM part 2587065010, only minimally improved the NOx reading. I do have EO approved exhaust headers, so there is only one cat with these headers the secondary larger one. There is two cats on the OEM set up, as there is additional cat that is on the crossover on the OEM exhaust system that runs from the passenger side to the merge manifold on the drivers side. I believe California may have approved these headers without actual having confirmed they were actually functional. What ever the case I'm also looking at the tire size, my truck had two options from the dealer, 31x 10.5 15 tires or 235 75 15 tires, the 235 75 15 tires are about a .5 to .75 inch smaller in diameter so the engine is effectively working harder at a lower rpm with the 31' tires on. I'm going to test again in 2 years with the new smaller tires as I was able to just barley squeak by their dyno test this past year.
Excellent Video! Thank you 50s kid. Quick question... everything seems to be working great now except for one thing. The only problem I'm running into is the final test when I hook up the three way to the EGR to tvv hose and I get no vacuum under power. I hook up straight to tvv I get vacuum under power. I even checked the EGR and it holds vacuum when not running and will stall if I provide vacuum while it is running. I am stumped! In a nutshell it seems as if EGR is good because it holds vacuum/ stalls when it should and the tvv hose is providing vacuum yet when I make the connection it shows no vacuum under power. I cannot explain it... Maybe you can
Man, this is so well done. There's something to be said about the satisfaction that comes from a proper diagnosis -- one that walks the fine line between being an effective procedure yet not being too convoluted and non-intuitive to understand like many factory service manual procedures can be. I'm picking up a vacuum pump like yours to run through this test on my '94 Toyota 4x4 pickup with the same 22RE engine, even though I don't have the code (did have the CEL come on for the first time a couple of weeks ago during a long stretch of constant speed, but it didn't come back upon restarting the truck and I haven't seen it since, so I doubt the ECU has stored the code in memory still). If there's any other videos you do / have done on that old Toyota 22RE, I'd be very interested in learning more.
The bulk head/firewall sticker shows the engine family and emissions group. The letter "N" is California but not on the vacuum routing chart that I have seen. A dead give-A-way is the screw-in temp sensor that goes into the EGR passage. A VSV controlled by the PCM is used to operate the EGR. At idle, like he did, open the EGR valve, the engine floods the combustion chamber with spent/burned exhaust and the engine dies. The EGR can be manually opened as well. No EGR with a cold engine regardless to RPM. The PCM/ECM based upon run time at road speed opens the EGR valve while steady RPM. It looks at the O2 sensor(s) to see the A/F turn lean as volumetric efficiency is affected. The Long Term/Short Term A/F graph is ignored during this short term. Again, if the Temp Sensor get hot, while the PCM is allowing or commanding it on, it means hot exhaust is flowing and working as designed. The ECM since 1992-1994 with OBD-2 starts test every solenoid/relay/thermistor's resistance matches appropriate range using voltage drop across relays coil, solenoids coil, in some cases resistance it is tested each time the engine is started. Most test run during the first 4-5 minutes of start. If air temp and coolant temp are within 10 degrees F of each other, this is cold start and many test are run. Some test like EVAP are run with fuel tank between 80-20% of full/empty at road speed. P1870 on auto slippage are ran full warm at road speed above 50 MPH while EVAP are ran with clock or "X" number of hours since last test, with tank not full/empty. The PCM/ECM module is very busy but remember that not all test ran & fail turn Check Engine Lamp on first fail. These do not threaten CAT but can be EVAP leaks like loose gas cap after refueling. So this is a lot to remember but a tech with good scan-tool has to check fail records. If test ran & fail, no light, type B code, but fail records captured. If fail of type "B" code means pending second fail, light comes on. This needs to be addressed. Otherwise, come-back due to dozens & dozens of codes type "A" or type "B". Great info, very good lighting and excellent clear testing techniques. Retired now but ASE Master Tech since 1978 (EFI/CIS/CARB)
So i was watching because my idle fluctuates when I hold the brake in the morning and some one said to check my vacuum system. I’m gonna take the same steps you just did and see what happens. Great video btw
You've probably figured it out already but your brake boaster is leaking. You can verify with the vacuum gauge. When you step on the brake, it's letting unmetered air into the system.
Thanks so much for this video, I followed each step and it passed them all, but for some reason when I put my gauge inline with the EGR the needle still doesn’t bounce with throttle. The line going into the egr has vacuum, the modulator has vacuum, and the truck shuts off when vacuum is applied to the egr. Can the tvv be failing even though it passed the hot/cold test? Thanks again
Hello, thanks for your video. One question, I have a 2008 Toyota Corolla with 230,000 km of manual gearbox. The fault is that when you turn it on it starts with 1300 rpm and as it warms up it goes up to 2000, that is, it does it the other way around since I understand it should go down to about 900 rpm. and when I'm hot I go out and when I make the gear changes I see that the rpm oscillates between 2000 and 1000 rpm and when I continue the march the minimum is 2000 rpm. If I leave it running stopped the car stays at 2000 rpm. I clarify that with a scanner it does not give an error. Well, we took out the carburetor, total cleaning including the filter's MAF sensor, I clarify that you can't take out the IAC valve to clean it, but the carburetor body was immersed in non-abrasive remover liquids and a lot of dirt came out. We measured TPS and IAC with a multimeter, simulated with power and everything was fine. We checked the pipes that had never been touched and were untouchable. We put everything together and it starts doing the same fault. Then I disconnected the EGR vacuum valve and there the rpm's dropped a little but after five seconds it accelerates and when connected it returns to 2000 rpm. Could it be a faulty EGR vacuum valve?
thanks, it took a few views for a novice like me to get it but I need to check my EGR on a 91 3.0 that shows a 25 code . having poor gas millage and some excess pressure in tank. already checked gas cap, vent line from tank and charcoal canister, changed 02 sensor. any suggestions if EGR checks out ok ?
Great video! Could you please tell me what the top screw thing that goes above the spring that is directly below the "E&F" letters on the block? My screw part above the spring broke and now it's a hole but I can't find any diagnostic that explains what that part is or it's function:(
By coincidence I replaced my 95 CAmry TVV after busting off one of the nipples for the vacuum hose. The only reasonably priced ones were used on Ebay. Days later (assuming it was a good TVV) I test drove the car and in 15 minutes I got a Check Engine Light. Got home it was a Code 71 (OBD1 on my era Camry)...EGR failure. I'm now suspicious the TVV I bought was not good or not compatible with my year. Any thoughts? ***BTW, a sensational explanation of this gen's EGR. I have looked EVERYWHERE online for info on the TVV, and you are the ONLY good fellow who have given an overview of the EGR plus the innocuous TVV. Most Toyota techs don't know what it is or how it works.
Great Job, every thing is perfect ,clear explanation do u have any idea about the emission system for Camry v6 2001?because the modulator and EGR built in together. thx
They've probably simplified it a bit. I haven't had the chance to work on it yet so I'm not familiar with what kind of system it is, whether it's electronic or still vacuum, I don't know.
Thank you So very much.MASTER! Outstanding.I am subbed but want you to know I think your teaching is super cool,Well explained...What do you think of removing the EGR system totally?I have No emission test here.Do you think there be a benefit?I see lots of folks on ebay sell egr blocking plates.TY73s
So could i just connect Q to the egr valve and run a vacuum line from intake vacuum to R? My BVSV valve is not working and i dont have the money, $89 plus tax, to replace it right now. I'm on a less than fixed income. Just wondering if the BVSV controls the amount, ie. 10 -psi,12.7 -psi, of vacuum. In other words, would too much vacuum pressure hinder the egr system? Thanks alot. Very excellent vid btw
Hey brother great video! I have a question I think you could answer. That 3 port vacuum port mounted on the intake manifold to the left of the egr valve. Where do those three lines go?
joshua corkum There are tons of different vacuum line configurations. The easiest way is to follow your vacuum diagram underhood sticker if you have one. If not, getting the correct diagram for your rig can be a little tricky. Mine was illegible except for the number 38 in the lower right corner of my sticker. Toyota has this info copyrighted and will not share it w toyota owners. If you still need the info and yours is illegible, let me know and I’ll give you some pointers on how to get the right info. It took me 6 months to find the correct layout for my rig after a mechanic screwed it up. I have much search experience! Lol
Can you do video on how to remove out that EGR value to clean? Looking at my Toyota Pickup 1994, seems there are three nuts in a triangle arrangement underneath it and it's hard to get to with a wrench or ratchet to unscrew them...
Exhaust gasses entering the combustion chamber doesn’t cool anything down, they’re ‘cooled’ in the egr cooler on the back of the head but they’re still entering the intake at 3 digit temps. It increases the temps in the combustion chamber and therefore increases EGTs even more, therefore reducing emissions by burning the gasses more efficiently. Remember A cold engine makes power, and a hot engine runs good and efficiently. Removing the entire assembly does in fact free up some power because you shouldn’t have to mash your pedal to the floor to have all the available power at your foots will.
hey man... good video, it gave me some good information to go by. Only thing is as I checked the egr, the modulator and vsv, they all checked out to be good. I'm getting codes p0401and p0300, p0302 and p0305 and I just can't seem to figure out what is going on, I'd appreciate some help very much. I have a 95 tocoma 3.4 4x4, when I crank it up in the morning it runs great, just like brand new but when it gets up to running temperature it starts running very rough and the check engine light starts flashing. Any ideas of what maybe causing the stumbling once it gets to running temperature?
Ok got an EGR problem. Got vacuum on all lines except for line R. Sprayed carb cleaner through line R and it is clean but is plugged at the throttle body. How does one removed the obstruction?
Hello, I have a 1996 Tacoma and it didn't pass the smog inspection by the code P0401 I have a question how many volts reach the VSV valve and if it always has to have current or there it is measured by Ohms
So when you jumped the VSV, where/what were the other ends of the jumper wires connected to? The battery? Or what? My truck is a 1986 22REI California Emissions. I don't have a Vacuum Hose Routing Diagram. :(
Yeah just the battery positive and negative. Remember to disconnect the valve before you jumper it. You should be able to find a hose routing diagram online
I’m getting vacuum pressure on P but not on R. When I connect in the end to the hose that meets the egr I’m getting no vacuum pressure? Does this sound like clogged lines or is the modulator failing somewhere and only producing some vacuum. I have a P0402 excessive flow egr.
Any chance you have a hpto of the vacuum tree that the hoses connect to? I found mis run of hoses from back of the tree to EGR. I cant see the tree end well enough to see which hose goes to the EGR itslef. I tried the pressure test on the TVV valve in cold and the pressure built up did not release by itself on my guage.
what I don't understand is why the engine died when you applied vacuum directly to the egr valve, yet when you fixed the problem and vacuum was being applied by the vacuum modulator it didn't die. Can anyone explain this?
I applied full vacuum to the valve, opening it completely, which introduced a large vacuum leak, which stalled the engine. When the system is working properly, the vacuum given to the valve is low at idle, thus the valve isn’t open very much. The valve needs to open more as engine speed increases (to suck more exhaust gasses in, to cool the engine down more and more), but of course engine vacuum diminishes the higher the speed gets, so that’s why it needs to use the exhaust backpressure to open the valve at that point. Did that all make sense?
This is by far the best explanation of EGR functions and diagnostic steps on UA-cam. Helped me a great deal in troubleshooting my son's 1994 Tacoma. Can't thank you enough!
fyi, first gen tacoma came out in '95, but close enough...lol
You taught me the difference between the TVV, and the VSV, and that these are always located between the EGR and the vacuum modulator. I learn something new everyday.
You are a gentleman and a scholar. I failed smog on my 1997 Toyota Tacoma, first time I had to replace the distributor cap and rotor, spark plugs and wires, but then I blew NO so much I was a gross polluter. I had no idea what to do, I replaced the air filter and cleaned the MAF sensor, still failed. Coming to this video, I bought a vacuum tool much like yours (not the cheap looking one, avoid), and it was my EGR valve that was stuck, like very dirty stuck, which I discovered when I tried to stall the engine by sucking on the ERG port. Long story short, I pull the EGR valve, cleaned it with carburetor cleaner, checked everything else per your video, and took it in for the 5th smog test, and it passed. Without your video I would have been lost. You are without a doubt a golden nugget of the internet, superb hands-on explanation.
Dudde, you are absolutely awesome! I spend days trying to learn about how the EGR and vacuum works, ...so confusing, but in 20 minutes I learn from you a lot.
Thanks for taking the time. Now im gonna try to fix the 71 code on my 91 Toyota 22re.
You really explain the EGR System very well. Thank you so much for sharing!
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This was and is a fantastic troubleshooting video. This helped me so much today working on a slow starting 1992 4Runner. I diagnosed, well you diagnosed, that my EGR was stuck closed. What I found was yes that was true, but also the back pressure port from the EGR to the modulator was clogged almost 100%. The hose also was nasty. Now I say that because I got vacuum off the back of the modulator and thought is was good. But still this video brought me to the problems, so Thank You!!!
I was impressed at the image quality and sound quality. You were easy to understand and follow! Thanks a ton for this video would love to see more videos on these toyotas!
I've got one coming up on diagnosing a misfire on this truck soon.
Thank you for being so clear about exactly how this works.
Thanks for the detailed lesson on EGR systems. I was wondering how it all worked and now that I know it's just that much easier to deal with the mess of vacuum hoses under the hood. One thing that helps too is just labeling the hoses and wires, I did mine with matching numbers at hose and connector, it took more time but in the end it will save time and headaches. This is my first rebuild and I had hoped just the top end needed work but unfortunately once I pulled the head off I diagnosed a rod knock in cylinder 2 as well so now I get to pull my first complete engine. I noticed in the process that my EGR valve was fossilized inside so it's why I searched ... I'm glad I stumbled onto your video. Great stuff! 🙏
WOW... thanks to your video, after a year and a half of trying to figure out why my pickup was throwing a code 71 and a lot of $ spent, I found out the shop that put a new head gasket in. Put the throttle body gasket on backwards, whichh gave a vacuum leak.
Thank you! I followed your directions and fixed the EGR on my 94 4Runner with the V6. I was able to pass emissions with flying colors! Thank you!!
Excellent vid. I have a 91 4x4 pickup with the same engine and for the first time ever, it failed tucson, az. emissions. I will check the egr system this morning. Thank technology for you tube and people like you for these videos
+jb good luck!
This is by far he best tutorial on the 22re egr system. Thank you for such a great video
Great video! Fixed the egr system on a 98 Camry recently and I wish I had known about this video! Ended up parts cannoning it and replacing all 3 components. It worked, the parts were cheap and there was no way I could figure out how that crazy system works and diagnose it properly. Now I know!
Great video. It helped me check out my system on my 91 pick up. Everything tested good but I was still getting a check engine lite. When I put vacuum to the egr valve it would hold vacuum but it wouldn't die barely a stumble. I removed egr valve cleaned out and tested. Tested good and reinstalled. Still had a lite and no die. I found out the clog was in the plenum. I removed the plenum and cleaned out the passage. It runs the length of the plenum and the other end of the passage is right behind the throttle body inside the plenum. Runs great, no lite, and dies whenever vacuum is applied to egr. Thanks for all the info.
Thanks 50sKid that was helpful. It is suprising how complex EFI is when you combine EGR with IAC and MAF and throttle position and vacuum.
I have a 3vze engine and with your explanation I feel good to diagnose my truck for code 71, thank you SR.
Best explanation of 22RE EGR diagnostic test I have seen, Thanks so much!
A lot of info packed in here. I'll be watching it more than once. Thanks for taking the time to share it!
Best video I’ve seen, explanation, understanding, now I’m more knowledgeable thanks
Excelent presentation. Guy definitely knows how it works.
Thank you.
Eight seconds in, you said, "It has some EGR problems." Like what ? Failed smog ? Rough idle ? Peeling paint ? Thanks. The video itself is really well made. Good sound, lighting, script, demonstrations. Thanks again.
failed smog for high NOx emissions. Sorry I wasn't more descriptive about that.
Thanks for responding. I got this goofy 1994 4 runner which passed smog but I Just realized that there IS NO PCV VALVE. Just a hose ! So I just added one. And there is no vacuum going to EGR modulator. I suspect the seller and smog test tech had a deal going. yikes
Just checked ... "P, E and R" vacuum ports on top of throttle body have NO vacuum, Even tho the other one right there does. I love a good mystery. Thanks again for your videos. Without it I would just take it to the shop. Boring.
Blow them out, clean out the passages with a fine steel wire like the strand from a bicycle brake cable. Blow them out with compressed air. You'll get your passes back. Then make sure your vacuum lines ain't clogged.
Wow! Outstanding video. Thank you so much for the clear explanation. I could have watched 100 other videos and not learned what I did from this one. Very well done. Excellent presentation. Thank you!
Man you are the Man! Im trying to learn as much as i can about my 94 4wd pickup with the 22re; and u have explained the egr more effectively than anyone thus far... im gonna check ur other vids. thanks!
NICE, It definitely helps me out! Thanks a lot for sharing. I'm trying to understand how the EGR works or not work.I have a California emissions 1986 and it has the temp-controlled VSV shown at 6:25. Toyota actually calls it the "Bimetallic Vacuum Switching Valve", hence VSV nomenclature on vacuum diagram.
You’re a legend. No other words do you justice.
Thanks 👍. On a trip atm and I had to stop for roadworks. Car idled very poorly, and when I drove off had no power with knocking. Stopped the engine and all came good when restarted Thanks to you I'll be able to find the culprit when home ...Cheers ! PS Toyota Avalon with vacumn EGR.
Nice troubleshooting steps. Very helpful.
Very excellent video.
My 92 Toyota pickup with 22RE looks exactly like the EGR system in the video. I am still not clear on which vacuum line is which for P and R that starts at the throttle body.
Anyway, this video helps me out a bunch. Next time I change head gasket or what ever all those vacuum lines are going bye bye.
This guy is like a teacher!! He is great!!!
Thanks for the education on this, otherwise I would've been lost. Good job!!!
Very clear explanation the step-by-step to get egr fix and save a couple $$ good job SR..😮very smart.
Excellent video got a 94 Toyota v6 truck with 3vze , just did valve covers now to check vacuum.
Best UA-cam video on here thank you
Best video by far! I’m so thankful! It helped me solve my problem.
Excellent coverage of the EGR system
Thank you so much for this. The 3vze 4Runner works on the same system. Mine has ZERO vacuum off the throttle body....
That's what is wrong with mine..u figure it out?.. im about to pull it off and clean it
Thanks for doing such a complete coverage 👍
amazing video. Thank you for explaining everything in detail. testing my egr system tomorrow
omg thank you for the knowledge! got a carbed 87 pu 22r with lots of vacuum lines... clear instructions and easy to follow! thanks
Thank you so much I failed smog after watching your video found out my TV valve was bad and just passed thank you so much
Superb!!! My 22re just failed smog , I’m going through step by step see what I can find THANKS!!!
Yet another excellent video!! You are definitely becoming one of my most favorite youtuber!
+12vgs8606 Thank you!
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Thank you.
Good and clear explaining.
Man! Great explanation! And that is a tough diagnosis!
Thanks. Thats a great video. Easy to follow and you did a really good job. i wish you did alot of videos on other things that are wrong with cars, trucks ect.
I will make it a point to do more in the future
Thank you for a really well done video! Nice clear video, lots of light and easy to follow along.
I'm heading to the garage now.
Very well explained thank you so much
Thanks 50'sKid- I'm a shade tree mechanic trying to solve Check Engine Light Code P0402. Happy Thanksgiving!
Thank you so much for making this video!
Incredibly Helpful, thank you.
The first thing to check when a P-0401 pops up is hoses - cracks defeat vacuum modulation. Second is the modulator: at some point [with age] the diaphragm of this will crack. You will get the code, and mileage will drop noticeably. With no dilution of intake air by exhaust gases, your O2 sensors will detect a lean condition, and long term fuel trim goes way up to compensate - its doubly worse than simple vacuum leaks on a system where EGR contol is working properly. If the above fails, solenoid valves may be the culprit - they may be a normally open or a normally closed design depending on engine
Having experienced the fullness of this fault, its depressing: a small, low power v6 engine... getting big block ford kind of mileage of 8-11mpg. New modulator brought back 16/21 mielage like it had when brand new.
Truck was maybe damaged on front CAL catalyst sticker is probably from a different vehicle.
Great video by the way very well done
Great video! My EGR is now deleted 😊
Awesome video! Good job
Going to test this tomorrow on my 86 pickup.
Failed California's smog check for too high Nox
Very easy to understand thanks
Excellent! Thank you. Perhaps that hood came from a Cali truck?
Very useful explanation !
Thanks for the great video!
Had nothing but problems with my 3vze engine 1993 T100 with high NOx smog etc, the EGR valve is opening, completely clear, replaced the EGR modulator with new valve OEM part 2587065010, only minimally improved the NOx reading. I do have EO approved exhaust headers, so there is only one cat with these headers the secondary larger one. There is two cats on the OEM set up, as there is additional cat that is on the crossover on the OEM exhaust system that runs from the passenger side to the merge manifold on the drivers side. I believe California may have approved these headers without actual having confirmed they were actually functional. What ever the case I'm also looking at the tire size, my truck had two options from the dealer, 31x 10.5 15 tires or 235 75 15 tires, the 235 75 15 tires are about a .5 to .75 inch smaller in diameter so the engine is effectively working harder at a lower rpm with the 31' tires on. I'm going to test again in 2 years with the new smaller tires as I was able to just barley squeak by their dyno test this past year.
Excellent Video! Thank you 50s kid. Quick question... everything seems to be working great now except for one thing. The only problem I'm running into is the final test when I hook up the three way to the EGR to tvv hose and I get no vacuum under power. I hook up straight to tvv I get vacuum under power. I even checked the EGR and it holds vacuum when not running and will stall if I provide vacuum while it is running. I am stumped! In a nutshell it seems as if EGR is good because it holds vacuum/ stalls when it should and the tvv hose is providing vacuum yet when I make the connection it shows no vacuum under power. I cannot explain it... Maybe you can
Thank you my awesome friend
Man, this is so well done. There's something to be said about the satisfaction that comes from a proper diagnosis -- one that walks the fine line between being an effective procedure yet not being too convoluted and non-intuitive to understand like many factory service manual procedures can be. I'm picking up a vacuum pump like yours to run through this test on my '94 Toyota 4x4 pickup with the same 22RE engine, even though I don't have the code (did have the CEL come on for the first time a couple of weeks ago during a long stretch of constant speed, but it didn't come back upon restarting the truck and I haven't seen it since, so I doubt the ECU has stored the code in memory still). If there's any other videos you do / have done on that old Toyota 22RE, I'd be very interested in learning more.
Very well done. Excellent video.
Well done,,Thanx much !!!
The bulk head/firewall sticker shows the engine family and emissions group. The letter "N" is California but not on the vacuum routing chart that I have seen.
A dead give-A-way is the screw-in temp sensor that goes into the EGR passage. A VSV controlled by the PCM is used to operate the EGR. At idle, like he did, open the EGR valve, the engine floods the combustion chamber with spent/burned exhaust and the engine dies. The EGR can be manually opened as well. No EGR with a cold engine regardless to RPM. The PCM/ECM based upon run time at road speed opens the EGR valve while steady RPM. It looks at the O2 sensor(s) to see the A/F turn lean as volumetric efficiency is affected. The Long Term/Short Term A/F graph is ignored during this short term. Again, if the Temp Sensor get hot, while the PCM is allowing or commanding it on, it means hot exhaust is flowing and working as designed.
The ECM since 1992-1994 with OBD-2 starts test every solenoid/relay/thermistor's resistance matches appropriate range using voltage drop across relays coil, solenoids coil, in some cases resistance it is tested each time the engine is started. Most test run during the first 4-5 minutes of start. If air temp and coolant temp are within 10 degrees F of each other, this is cold start and many test are run. Some test like EVAP are run with fuel tank between 80-20% of full/empty at road speed. P1870 on auto slippage are ran full warm at road speed above 50 MPH while EVAP are ran with clock or "X" number of hours since last test, with tank not full/empty.
The PCM/ECM module is very busy but remember that not all test ran & fail turn Check Engine Lamp on first fail. These do not threaten CAT but can be EVAP leaks like loose gas cap after refueling. So this is a lot to remember but a tech with good scan-tool has to check fail records. If test ran & fail, no light, type B code, but fail records captured. If fail of type "B" code means pending second fail, light comes on. This needs to be addressed. Otherwise, come-back due to dozens & dozens of codes type "A" or type "B". Great info, very good lighting and excellent clear testing techniques.
Retired now but ASE Master Tech since 1978 (EFI/CIS/CARB)
So i was watching because my idle fluctuates when I hold the brake in the morning and some one said to check my vacuum system. I’m gonna take the same steps you just did and see what happens. Great video btw
You've probably figured it out already but your brake boaster is leaking. You can verify with the vacuum gauge. When you step on the brake, it's letting unmetered air into the system.
Excellent Video!!!
Thanks so much for this video, I followed each step and it passed them all, but for some reason when I put my gauge inline with the EGR the needle still doesn’t bounce with throttle. The line going into the egr has vacuum, the modulator has vacuum, and the truck shuts off when vacuum is applied to the egr. Can the tvv be failing even though it passed the hot/cold test? Thanks again
Hello, thanks for your video. One question, I have a 2008 Toyota Corolla with 230,000 km of manual gearbox. The fault is that when you turn it on it starts with 1300 rpm and as it warms up it goes up to 2000, that is, it does it the other way around since I understand it should go down to about 900 rpm. and when I'm hot I go out and when I make the gear changes I see that the rpm oscillates between 2000 and 1000 rpm and when I continue the march the minimum is 2000 rpm. If I leave it running stopped the car stays at 2000 rpm. I clarify that with a scanner it does not give an error. Well, we took out the carburetor, total cleaning including the filter's MAF sensor, I clarify that you can't take out the IAC valve to clean it, but the carburetor body was immersed in non-abrasive remover liquids and a lot of dirt came out. We measured TPS and IAC with a multimeter, simulated with power and everything was fine. We checked the pipes that had never been touched and were untouchable. We put everything together and it starts doing the same fault. Then I disconnected the EGR vacuum valve and there the rpm's dropped a little but after five seconds it accelerates and when connected it returns to 2000 rpm. Could it be a faulty EGR vacuum valve?
thanks, it took a few views for a novice like me to get it but I need to check my EGR on a 91 3.0 that shows a 25 code . having poor gas millage and some excess pressure in tank. already checked gas cap, vent line from tank and charcoal canister, changed 02 sensor. any suggestions if EGR checks out ok ?
Thanks for the video I learn a lot today👍👍👍👍
Great video! Could you please tell me what the top screw thing that goes above the spring that is directly below the "E&F" letters on the block? My screw part above the spring broke and now it's a hole but I can't find any diagnostic that explains what that part is or it's function:(
Great job !! Tanks a lot for your help !!
Thank you so much. If anyone needs this with spanish subtitles, just let me know.
By coincidence I replaced my 95 CAmry TVV after busting off one of the nipples for the vacuum hose. The only reasonably priced ones were used on Ebay. Days later (assuming it was a good TVV) I test drove the car and in 15 minutes I got a Check Engine Light. Got home it was a Code 71 (OBD1 on my era Camry)...EGR failure. I'm now suspicious the TVV I bought was not good or not compatible with my year. Any thoughts?
***BTW, a sensational explanation of this gen's EGR. I have looked EVERYWHERE online for info on the TVV, and you are the ONLY good fellow who have given an overview of the EGR plus the innocuous TVV. Most Toyota techs don't know what it is or how it works.
Great Job, every thing is perfect ,clear explanation do u have any idea about the emission system for Camry v6 2001?because the modulator and EGR built in together. thx
They've probably simplified it a bit. I haven't had the chance to work on it yet so I'm not familiar with what kind of system it is, whether it's electronic or still vacuum, I don't know.
Thank you So very much.MASTER! Outstanding.I am subbed but want you to know I think your teaching is super cool,Well explained...What do you think of removing the EGR system totally?I have No emission test here.Do you think there be a benefit?I see lots of folks on ebay sell egr blocking plates.TY73s
When testing the VSV , what are the red and black jumpers connected to? The battery?
How did you jumper the valve on your checking valve switch? We didn’t see it. Are you talking about power conector or vacuum T conector at some point?
So could i just connect Q to the egr valve and run a vacuum line from intake vacuum to R? My BVSV valve is not working and i dont have the money, $89 plus tax, to replace it right now. I'm on a less than fixed income. Just wondering if the BVSV controls the amount, ie. 10 -psi,12.7 -psi, of vacuum. In other words, would too much vacuum pressure hinder the egr system? Thanks alot. Very excellent vid btw
Hey brother great video! I have a question I think you could answer. That 3 port vacuum port mounted on the intake manifold to the left of the egr valve. Where do those three lines go?
joshua corkum There are tons of different vacuum line configurations. The easiest way is to follow your vacuum diagram underhood sticker if you have one. If not, getting the correct diagram for your rig can be a little tricky. Mine was illegible except for the number 38 in the lower right corner of my sticker. Toyota has this info copyrighted and will not share it w toyota owners. If you still need the info and yours is illegible, let me know and I’ll give you some pointers on how to get the right info. It took me 6 months to find the correct layout for my rig after a mechanic screwed it up. I have much search experience! Lol
How much voltage did you apply to the vsv to actuate it? And/or how do you figure how much voltage to apply?
Can you do video on how to remove out that EGR value to clean? Looking at my Toyota Pickup 1994, seems there are three nuts in a triangle arrangement underneath it and it's hard to get to with a wrench or ratchet to unscrew them...
CAN YOU PLEASE explain why engine stalls when you pull vacuum on a good EGR valve?
Great video.
wow great job mine just failed smog so i tested the EGR valve and the engine keeps running
Exhaust gasses entering the combustion chamber doesn’t cool anything down, they’re ‘cooled’ in the egr cooler on the back of the head but they’re still entering the intake at 3 digit temps. It increases the temps in the combustion chamber and therefore increases EGTs even more, therefore reducing emissions by burning the gasses more efficiently. Remember A cold engine makes power, and a hot engine runs good and efficiently. Removing the entire assembly does in fact free up some power because you shouldn’t have to mash your pedal to the floor to have all the available power at your foots will.
hey man... good video, it gave me some good information to go by. Only thing is as I checked the egr, the modulator and vsv, they all checked out to be good. I'm getting codes p0401and p0300, p0302 and p0305 and I just can't seem to figure out what is going on, I'd appreciate some help very much. I have a 95 tocoma 3.4 4x4, when I crank it up in the morning it runs great, just like brand new but when it gets up to running temperature it starts running very rough and the check engine light starts flashing. Any ideas of what maybe causing the stumbling once it gets to running temperature?
Ok got an EGR problem. Got vacuum on all lines except for line R.
Sprayed carb cleaner through line R and it is clean but is plugged at the throttle body. How does one removed the obstruction?
How do you jump the VSV, with 12V car battery? Is battery polarity matter when jumping the VSV?
Thank you very much!
Hello, I have a 1996 Tacoma and it didn't pass the smog inspection by the code P0401 I have a question how many volts reach the VSV valve and if it always has to have current or there it is measured by Ohms
So when you jumped the VSV, where/what were the other ends of the jumper wires connected to? The battery? Or what? My truck is a 1986 22REI California Emissions. I don't have a Vacuum Hose Routing Diagram. :(
Yeah just the battery positive and negative. Remember to disconnect the valve before you jumper it. You should be able to find a hose routing diagram online
Thank you Sir.
I’m getting vacuum pressure on P but not on R. When I connect in the end to the hose that meets the egr I’m getting no vacuum pressure? Does this sound like clogged lines or is the modulator failing somewhere and only producing some vacuum. I have a P0402 excessive flow egr.
Any chance you have a hpto of the vacuum tree that the hoses connect to? I found mis run of hoses from back of the tree to EGR. I cant see the tree end well enough to see which hose goes to the EGR itslef.
I tried the pressure test on the TVV valve in cold and the pressure built up did not release by itself on my guage.
When I put vacuum to the egr vavle, the engine doesn’t stall, but runs real rough. Does that mean it’s not working properly?
my vacum modulator is open all the time, can see light through it. does that mean it's bad? even when there is no pressure.
what I don't understand is why the engine died when you applied vacuum directly to the egr valve, yet when you fixed the problem and vacuum was being applied by the vacuum modulator it didn't die. Can anyone explain this?
I applied full vacuum to the valve, opening it completely, which introduced a large vacuum leak, which stalled the engine. When the system is working properly, the vacuum given to the valve is low at idle, thus the valve isn’t open very much. The valve needs to open more as engine speed increases (to suck more exhaust gasses in, to cool the engine down more and more), but of course engine vacuum diminishes the higher the speed gets, so that’s why it needs to use the exhaust backpressure to open the valve at that point. Did that all make sense?