I am a retired Jet engine engineer and have worked with everything from a chain saw to a 747 turbo fan engine. I have been to many factory schools on engines. You my friend are clearly on a paralel with them with your knowledge of your topic and ease of providing an extreamly understandable explination. You are to be comended. Thank you for this service you provide us retirees that are now auto tinkerers. Good luck and Thanks.
Thank you very much for the kind words I appreciate it very much. I am very happy to help out. I hope to help you out more in the future. If you every have any specific questions or requests please feel free to message me on my Instagram and I will be happy to get back to you. Thank you for watching.
I really appreciate this video. For decades now vacuum leaks have been mysterious to me, but recently I realized that my truck a/c had failed due to a vacuum leak which I fixed myself today. A/C works perfectly again. About the same time the a/c failed I noticed 171 & 174 lean codes caused my engine light to come on. So I came to your video wondering if the broken vacuum line that caused my a/c to fail could also have caused the 171 & 174 lean codes. Ultimately you didn’t answer my quest, but you took away a lot of the mystery about vacuum leaks in general & helped me in other ways & since my truck has the same engine, that’s a big deal to me. Anyway, I reset the lean codes after fixing my vacuum line leak & we’ll see if they return. If so I’ll tackle that later with help from yourself & others. You made an instant sub out of me.
First thing to know about lean codes is you have to look at the freeze frame to see when the codes set. If they set at idle then most likely looking at vacuum leaks or maf sensor. If at while driving under load then possibly fuel pump, fuel filter or maf sensor. Seeing the freeze frame is imperative to diagnosing this. Message me on Instagram if you have any questions. Thanks for watching
I'm a pure rookie that just bought a 2001 f150 that's running poor with 171, 174 codes so you learned me a lot! 😝 Really good diag info to start with! Thank you man!
Best video I appreciate you making this video!! I'm dealing with this problem on my 1996 f150 4.9l straight six.. mechanics just keep charging and no fix about $2000.00 in already..it is so frustrating... But my truck runs like a champion and I am the original owner. I will not give up on her (trucK).lol I have decided to start working on this issue my self. again thank you for sharing old school knowledge.. Thank you.
Wow, I was looking around for a simple answer that I might want to do myself. I learned something - let my mechanic do his job, he's good at it. Thanks though, this was really interesting, since my truck is getting pretty old now. you explained it well.
excellent video. I recently found out that a loose/leaking oil filler cap and/or oil filler tube grommet seal failure- can be a source of unmonitored intake air.
@@NutsandBoltswithTone however - doing a smoke test into the air intake, after the MAF sensor, smoke will come out of the oil filler, w cap off (I saw in a youtube video) and realized my cap was not firmly sealing. Thoughts?
@atomicdmt8763 you have to block off the fresh air tube from the air intake. Between your throttle body and air filter there is a hose that connects to a valve cover. That goes to the crankcase, you don't want smoke to go into the crankcase only the intake system. So you have to block that somehow. Message me on Instagram if you need more help
@@NutsandBoltswithTone this still begs the question/concern: air leaks from the crankcase/filler tube/filler cap could be an unmonitored air issue. Correct?
I just bought a 01 Navigator with 130k miles... I just replaced the fuel pump with a Delphi unit. I did not drop/clean the tank. I am getting 171/174. Something to note here is that the fuel gauge turns off/on. I get 174 at idle, it is very lean around +20 LTFT. At idle bank 1 is around +/- 5% for both LTFT/STFT. On WOT, bank 2 is +/- 4% both both LTFT and STFT. At WOT, bank 1 leans out. At cruising, they are both lean. If I let off the gas after WOT suddenly it sputters and backfires. Sometimes the fuel trims go to +50%!!! Something else to note is the Catilitic converters were taken off and you can see both O2 sensors under the truck (they are still screwed into the exhaust pipes).
Very informative n straight to the point, I am learning a lot from you man little by little I am so thankful I stumble on your video, just sub to you n thank You for teaching all of us n more power to your show😁👍👍
Mine was exhaust leaks at the manifold to collector on my 2003 Mach1 Mustang. This was after a local exhaust shop installed an SLP x pipe and didn’t follow the installation instructions.
@NutsandBoltswithTone I just ordered on oem. But pulled the plugs and it's running lean. Hard cold starts, and weird idle when warmed up. So we'll hope that fixes the issue. Not really wanting to pull the manifold unless necessary.
2:08 "You can't clean them." I've never had a problem with cleaning them, even some that were super grungy and making the engine run like crap. After cleaning the engines ran fine and fuel trims were near 0.
@DonziGT230 you can partially clean them that lasts a short time, but cannot clean them completely. But yes you can spray them and make an immediate difference
I Have the 2005 Ford sport trac same engine and the same problem, I did a smoke test all is sealed but I do have leaks at the throttle body shaft just like yours maybe not as bad but its doing it( Obsolete part) would this cause the high trims by it self or is it something else ?
The throttle shaft is going to have some leakage just depends on how much. Mine had quite a bit. To answer your question you have to see if your fuel trims are high at idle with throttle closed or open. Sometimes vacuum leaks do not show when cold or sometimes hot. Your Mass Airflow Sensor could be incorrectly reporting. You can message me on Instagram and I can help you further. Thanks for watching.
Well you have to determine if it is just a bank 2 problem p0174 or if there is also a problem sith bank 1 as well p0171. Then you have to determine if code sets at idle or driving etc, thanks for watching the video
The only way I could see these codes having anything to do with cutting off is if the fuel pump is going out, so you have lean condition due to lack of fuel and then completely quits working. I do not think that is the cause though. Thank you for watching.
I have a 04 ranger 3.0 code P0174 lean on bank 2. Can’t figure out what it is. New O2 sensors, new exhaust manifolds and gaskets, new PCV, spark plugs and wires, new MAF sensor, new fuel injectors, fuel pump, fuel filter all parts are Ford brand Motorcraft. Any suggestions??
I have a 01 ranger 3.0 and did everything you did except injectors and pump but i also did the EGR and trans because it wasn’t shifting into reverse or anything but I just got the same code
@@Ty-bw9sw mine doesn’t have an EGR luckily. I’ve done a smoke test on the engine and exhaust nothing. Im thinking it’s either an evap failure or pcm. It’s weird cause once I take the gas cap off the fuel trim drops to around 10- 8 but long term fuel trim just on bank 2 stays at 30 at idle. When I press the gas short term fuel trim bank 2 goes to 28 and long term drops to 10-8 then once I let off it goes back to what it originally was. I lost on this one, I’ve been working on vehicles my whole life and never had this hard of a diagnosis. Im thinking about take to the Ford dealer to have them try to reflash the pcm or update it if there’s an update available
Currently having this problem on my 96 crown Vic. I changed those things also and it’s still coming on. What could it be? Tired of spending money and it’s not fixing the problem.
@@NutsandBoltswithTone dang, I’m having issues with bank 2 running lean P0174 on my 04 ranger 3.0. Can’t figure out what it is.I’ve replaced the fuel injectors, PCV, MAF sensor, fuel pump and fuel filter, new ignition coil, new spark plugs, new air filter and new bank 2 02 sensors. All parts are Motorcraft Ford brand as well. Any suggestions??
@@NutsandBoltswithTone long term fuel trim 1 reads 3.9%short term fuel trim bank 1 reads 0% bank 2 long term reads 21.9% short term fuel fuel trim bank 2 reads. 25% bank 2 sensor 2 reads 0.815 volts bank 2 sensor 1 reads 0.760 volts
@@NutsandBoltswithTone wish I'd have known you were in Sactown a couple years ago...just moved to Ohio from Santa Rosa! I got an 89 Bronco with a 96 351 swap that has lean 1 and 2 codes... Still trying to nail it down! This videos helps.
You mentioned temperature could be a culprit. Could you get a lien code because the engine never comes up to temp? My 5.4 l. Ford is only reaching about 140° and my scanner says the fuel mixture is in closed loop and operating off the O2 sensors. I have a new thermostat on the way. as a first step.
Thermostat replacement is a must as first step however if the pcm is showing closed loop then it is probably not the issue. It is a possibility but not likely. I would replace thermostat and recheck. Hit me up on Instagram if you need any help. Thanks for watching.
Thanks for the reply. I changed the Thermostat today. I went from running 140 degrees to 180-183 degrees. I just test drove enough to check for leaks. I'll do more extensive driving and rescan for codes tomorrow.@@NutsandBoltswithTone
Oh ok man,you gave me some great ideas to look at on my 01 ford pu 5.4,my service engine light pops on when idling,took it to parts house they scanned it,it come up with po171 and po174 codes and said to change my pcv valve,I changed it cleared the codes it came back on a week later when I was at a red light,so tomorrow I'll look at my maf sensor just to see,but dude I really wish I had one of those smoke thingamajigs like you have cause I'm starting to think I gotta vacuum leak somewhere,but dude I appreciate all the ideas you explained in your video,it really opened my eyes to some things to look at,GOD BLESS guy,and Thanks again for your helpful knowledge,PEACE OUT👌😃
I am a retired Jet engine engineer and have worked with everything from a chain saw to a 747 turbo fan engine. I have been to many factory schools on engines. You my friend are clearly on a paralel with them with your knowledge of your topic and ease of providing an extreamly understandable explination. You are to be comended. Thank you for this service you provide us retirees that are now auto tinkerers. Good luck and Thanks.
Thank you very much for the kind words I appreciate it very much. I am very happy to help out. I hope to help you out more in the future. If you every have any specific questions or requests please feel free to message me on my Instagram and I will be happy to get back to you. Thank you for watching.
I really appreciate this video. For decades now vacuum leaks have been mysterious to me, but recently I realized that my truck a/c had failed due to a vacuum leak which I fixed myself today. A/C works perfectly again. About the same time the a/c failed I noticed 171 & 174 lean codes caused my engine light to come on. So I came to your video wondering if the broken vacuum line that caused my a/c to fail could also have caused the 171 & 174 lean codes. Ultimately you didn’t answer my quest, but you took away a lot of the mystery about vacuum leaks in general & helped me in other ways & since my truck has the same engine, that’s a big deal to me.
Anyway, I reset the lean codes after fixing my vacuum line leak & we’ll see if they return. If so I’ll tackle that later with help from yourself & others.
You made an instant sub out of me.
First thing to know about lean codes is you have to look at the freeze frame to see when the codes set. If they set at idle then most likely looking at vacuum leaks or maf sensor. If at while driving under load then possibly fuel pump, fuel filter or maf sensor. Seeing the freeze frame is imperative to diagnosing this. Message me on Instagram if you have any questions. Thanks for watching
I'm a pure rookie that just bought a 2001 f150 that's running poor with 171, 174 codes so you learned me a lot! 😝
Really good diag info to start with! Thank you man!
Thank you very much. I appreciate you watching. If you have any other questions feel free to message me on Instagram and I will help you over there.
Best video I appreciate you making this video!! I'm dealing with this problem on my 1996 f150 4.9l straight six.. mechanics just keep charging and no fix about $2000.00 in already..it is so frustrating... But my truck runs like a champion and I am the original owner. I will not give up on her (trucK).lol I have decided to start working on this issue my self. again thank you for sharing old school knowledge.. Thank you.
My pleasure, if you have any questions hit me up on Instagram and I will see if I can help you out. Thank you for watching.
Thanks partner for this info. I have a 200 Explorer with a lean bank 2 code. I will now try to trace it down.
Awesome, thank you for watching and good luck
Wow, I was looking around for a simple answer that I might want to do myself. I learned something - let my mechanic do his job, he's good at it. Thanks though, this was really interesting, since my truck is getting pretty old now. you explained it well.
Man this guy is good...I can tell he knows his stuff. Thank's for sharing this info. Definitely got my subscription and like..👍🏾
I appreciate the kind words thank you very much. I appreciate you watching
Great video! I'm definitely putting my original maf sensor back in and tossing the cheap aftermarket one. Thanks again 👍
You are very welcome and I am very happy to help. Thank you for watching the video. I appreciate it.
Extremely informative video. Thank you for this. Definitely learned something new today
Glad it was helpful!
Good video, Tony. I like the case studies, keep ‘em coming.
Thank you Steve, I appreciate it. Thank you for watching.
Thank you very much for the info man! Well spoken, good info, no fluff. Perfect
Thank you so much. I appreciate ya watching.
excellent video. I recently found out that a loose/leaking oil filler cap and/or oil filler tube grommet seal failure- can be a source of unmonitored intake air.
A loose oil fill cap should not cause this in this engine. Now in european cars for sure.
@@NutsandBoltswithTone however - doing a smoke test into the air intake, after the MAF sensor, smoke will come out of the oil filler, w cap off (I saw in a youtube video) and realized my cap was not firmly sealing. Thoughts?
@atomicdmt8763 you have to block off the fresh air tube from the air intake. Between your throttle body and air filter there is a hose that connects to a valve cover. That goes to the crankcase, you don't want smoke to go into the crankcase only the intake system. So you have to block that somehow. Message me on Instagram if you need more help
@@NutsandBoltswithTone thanks - that makes sense. Ill try blocking this air intake tube and doing the smoke test again.
@@NutsandBoltswithTone this still begs the question/concern: air leaks from the crankcase/filler tube/filler cap could be an unmonitored air issue. Correct?
I learned a lot from this video , TY very much for sharing your knowledge
I am very happy to help. Thank you for watching.
Great knowledge, very experienced Technician.
Thank you very much. I appreciate you watching. Message me on Instagram if you have any questions
I just bought a 01 Navigator with 130k miles... I just replaced the fuel pump with a Delphi unit. I did not drop/clean the tank. I am getting 171/174. Something to note here is that the fuel gauge turns off/on.
I get 174 at idle, it is very lean around +20 LTFT. At idle bank 1 is around +/- 5% for both LTFT/STFT.
On WOT, bank 2 is +/- 4% both both LTFT and STFT. At WOT, bank 1 leans out.
At cruising, they are both lean. If I let off the gas after WOT suddenly it sputters and backfires. Sometimes the fuel trims go to +50%!!!
Something else to note is the Catilitic converters were taken off and you can see both O2 sensors under the truck (they are still screwed into the exhaust pipes).
Freeze frame data for P0171:
CL Fuel System
Load Pct 48.6
ECT 77*C
STFT1: 9.4
LTFT1 : 28.9
STFT2: 8.6
LTFT2 29.7
RPM 1611
VSS 34 kMh
Sorry to hear about your troubles if you can message me on Instagram I can help you. It's much easier. Thx for watching
Very informative! Thanks. 👏🏼👏🏼👏🏼🎯
Thank you very much. I appreciate you watching.
Thanks Champ you got straight to the point my dude very informative keep up the great content 💯💪🏿 subscribed
Thank you very much I really appreciate it. Thank you for watching.
Very informative n straight to the point, I am learning a lot from you man little by little I am so thankful I stumble on your video, just sub to you n thank You for teaching all of us n more power to your show😁👍👍
Well thank you very much I am very happy to help. I appreciate you watching and hope to teach you more in the future. Thank you for watching.
Well done, thank you
Thank you and I appreciate you watching m
Great information.
Thank you very much I appreciate that, thank you for watching
Mine was exhaust leaks at the manifold to collector on my 2003 Mach1 Mustang. This was after a local exhaust shop installed an SLP x pipe and didn’t follow the installation instructions.
Oh wow that is a bummer that they caused the issues. Yes improperly installed exhaust kits can cause some issues. Thank you for watching.
Great information. Appreciate it..
Thank you and I appreciate you watching.
My 2000 Ford Explorer 4.0 is having this issue. The previous owner out an aftermarket mass air flow on and sets on idle.
aftermarket maf sensors are no good.
@NutsandBoltswithTone I just ordered on oem. But pulled the plugs and it's running lean. Hard cold starts, and weird idle when warmed up. So we'll hope that fixes the issue. Not really wanting to pull the manifold unless necessary.
you da man,thank you
You are very welcome. Thanks for watching.
I changed my oxygen sensor I changed my mass air flow sensor I change my air filter
2:08 "You can't clean them." I've never had a problem with cleaning them, even some that were super grungy and making the engine run like crap. After cleaning the engines ran fine and fuel trims were near 0.
@DonziGT230 you can partially clean them that lasts a short time, but cannot clean them completely. But yes you can spray them and make an immediate difference
Nice vid, what your thoughtsv on p01130 P01131 01 towncar
Not 100 percent sure off the top of my head. If you message me on Instagram with the vehicle info I can try to help. Thx for watching
Good video👍
Glad you enjoyed, thank you for watching.
I Have the 2005 Ford sport trac same engine and the same problem, I did a smoke test all is sealed but I do have leaks at the throttle body shaft just like yours maybe not as bad but its doing it( Obsolete part) would this cause the high trims by it self or is it something else ?
The throttle shaft is going to have some leakage just depends on how much. Mine had quite a bit. To answer your question you have to see if your fuel trims are high at idle with throttle closed or open. Sometimes vacuum leaks do not show when cold or sometimes hot. Your Mass Airflow Sensor could be incorrectly reporting. You can message me on Instagram and I can help you further. Thanks for watching.
hello i am having this chrysler 200 with a bank 1 air fuel ratio inbalance code is p219A
You need to scan it, check the data first. Thanks for watching.
Good video
Thank you Brotha, I really appreciate you watching and the comment.
do you know how to fix po code 174 ?
Well you have to determine if it is just a bank 2 problem p0174 or if there is also a problem sith bank 1 as well p0171. Then you have to determine if code sets at idle or driving etc, thanks for watching the video
What kind of scanner is it
Snap on modis I think
Will these codes cause the vehicle to cut-off ? I have a P0 171/P0 174 in my ,2012 Ford E-350
The only way I could see these codes having anything to do with cutting off is if the fuel pump is going out, so you have lean condition due to lack of fuel and then completely quits working. I do not think that is the cause though. Thank you for watching.
Great info brother new sub
Thank you very much. I appreciate you watching.
I have a 04 ranger 3.0 code P0174 lean on bank 2. Can’t figure out what it is. New O2 sensors, new exhaust manifolds and gaskets, new PCV, spark plugs and wires, new MAF sensor, new fuel injectors, fuel pump, fuel filter all parts are Ford brand Motorcraft. Any suggestions??
I can for sure help you. it is easier to communicate on instagram so go to my insta and message me and I will walk you through how to figure it out.
I have a 01 ranger 3.0 and did everything you did except injectors and pump but i also did the EGR and trans because it wasn’t shifting into reverse or anything but I just got the same code
@@Ty-bw9sw mine doesn’t have an EGR luckily. I’ve done a smoke test on the engine and exhaust nothing. Im thinking it’s either an evap failure or pcm. It’s weird cause once I take the gas cap off the fuel trim drops to around 10- 8 but long term fuel trim just on bank 2 stays at 30 at idle. When I press the gas short term fuel trim bank 2 goes to 28 and long term drops to 10-8 then once I let off it goes back to what it originally was. I lost on this one, I’ve been working on vehicles my whole life and never had this hard of a diagnosis. Im thinking about take to the Ford dealer to have them try to reflash the pcm or update it if there’s an update available
Bad cat
Currently having this problem on my 96 crown Vic. I changed those things also and it’s still coming on. What could it be? Tired of spending money and it’s not fixing the problem.
👍👍👍
Thank you for watching.
You in VA?
I'm actually in Sacramento California.
@@NutsandBoltswithTone dang, I’m having issues with bank 2 running lean P0174 on my 04 ranger 3.0. Can’t figure out what it is.I’ve replaced the fuel injectors, PCV, MAF sensor, fuel pump and fuel filter, new ignition coil, new spark plugs, new air filter and new bank 2 02 sensors. All parts are Motorcraft Ford brand as well. Any suggestions??
@@NutsandBoltswithTone long term fuel trim 1 reads 3.9%short term fuel trim bank 1 reads 0% bank 2 long term reads 21.9% short term fuel fuel trim bank 2 reads. 25% bank 2 sensor 2 reads 0.815 volts bank 2 sensor 1 reads 0.760 volts
@@NutsandBoltswithTone wish I'd have known you were in Sactown a couple years ago...just moved to Ohio from Santa Rosa!
I got an 89 Bronco with a 96 351 swap that has lean 1 and 2 codes... Still trying to nail it down! This videos helps.
You mentioned temperature could be a culprit. Could you get a lien code because the engine never comes up to temp? My 5.4 l. Ford is only reaching about 140° and my scanner says the fuel mixture is in closed loop and operating off the O2 sensors. I have a new thermostat on the way. as a first step.
Thermostat replacement is a must as first step however if the pcm is showing closed loop then it is probably not the issue. It is a possibility but not likely. I would replace thermostat and recheck. Hit me up on Instagram if you need any help. Thanks for watching.
Thanks for the reply. I changed the Thermostat today. I went from running 140 degrees to 180-183 degrees. I just test drove enough to check for leaks. I'll do more extensive driving and rescan for codes tomorrow.@@NutsandBoltswithTone
@keithbrookshire awesome work, keep me posted on the codes.
Dude,are you in Alabama?
I am in Sacramento California.
Oh ok man,you gave me some great ideas to look at on my 01 ford pu 5.4,my service engine light pops on when idling,took it to parts house they scanned it,it come up with po171 and po174 codes and said to change my pcv valve,I changed it cleared the codes it came back on a week later when I was at a red light,so tomorrow I'll look at my maf sensor just to see,but dude I really wish I had one of those smoke thingamajigs like you have cause I'm starting to think I gotta vacuum leak somewhere,but dude I appreciate all the ideas you explained in your video,it really opened my eyes to some things to look at,GOD BLESS guy,and Thanks again for your helpful knowledge,PEACE OUT👌😃