Check Engine Light, No Symptoms on Your Car? Diagnose Code P0171 Low Fuel Trim

Thanks I thought I had to replace a fuel pimp

1997 honda accord, 171 code after stalling on a puddle of water. Low Idle,up and down is minor still noticeable if you inside the car,

Very helpful!

This just happened to me im going look at this in the morning

I HAVE AN ACURA RL 2006, MY LIGHT ENGINE TURNED ON AND ON LETTERS ON MY DASH BOARD SAID (CHECK EMISSION SISTEM), THE MECHANIC WHO WORKS ON MY CAR SCANNED IT AND HAD THUS CODES (P0171 AND P0171) HE SAID IS THE OXIGEN SENSOR AND MAF SENSOR SO I SPEND $600 AND BUY IT 4 OXIGEN SENSOR AND MAF SENSOR NEW AND ORIGINAL, HE MOUNT IT AND ERASE CODES... AFTER 40 MINUTES IT START SHOW UP AGAIN ENGINE LIGHT ON AND SAID THE SAME AS BEFORE, (CHECK EMISSION SISTEM)... IM CRAZY WITH IT. THE CAR RUNS PERFECT, NO SHAKING MOTOR, THE TACOMETTER IS 750 AND I DONT FEEL ANY PROBLEM ECEPT SHECK ENGINE LIGHT WITH SHECK EMISSION SISTEM... WHAT ELSE CAN I DO SO I WONT TO SPEND MORE MONEY ON IT, ANY ADVICE PLEASE ?

Thank you so much for this, got the P0171 on my 09 Acura TL, checked around my air box and intake hose and wouldn't you know it there was a giant slit in the air intake hose (probably happened during last oil change), wrapped hole in electrical tape for time being and ordered part, $35 on Amazon, RockAuto didn't have it for some reason. Seen people say that it's a leak after the MAF, in my case, was the issue, The next 2 issues it could be is bad or clogged MAF or O2 sensor, 9 times out of 10 it's a leak though - unmetered air getting in.

Ghthhhy

Thanks for the video!! I have same issue with my 2014 Mercedes c250. P0171 code came up but running like a champ. Noticed air box around filter was slightly ajar. Don’t see any other loose hoses. I tightened air box to see if this was the problem. should the check engine light go away on its own or do I have to erase the code?

Had this code happen on a lexus CT200h. Checked all hoses, Replaced a PCV it was sticky and as well as the MAF sensor but Not sure what it was but not those as the problem persisted and I stopped running down the rabbit hole. Gets frustrating sometimes

my Silverado says P0171 system too lean

Hello good morning I have a question I replace my engine I have a 2014 dodge ram 5.7 don't start I have code u1477-00 p1b13 help me please

Just recently purchased a Insignia 1.8. Engine light came on then off, but now its back on - P0171 code showing on scanner. Going to try this before taking it to a mechanic. 👍

Do I have to rotate engine to TDC before I smoke test the intake manifold? Or no need to,?
Reason why I’m asking is because on this lexus 3,0 I’m getting smoke out of oil fill & oil dip stick.

Brother thank you. My light went on after my oil change. I went under my hood and yup those ding dongs forgot to tighten up my cover on my air filter. Thank you, you saved me about 1000 bucks.

My longft is at almost 40%, can anyone link a good video?

What could be the cause of a P0171 on a 2016 Jeep Patriot Latitude 2.0 we just replaced the MAP sensor but the vehicle still has a rough idle and the rpms run high while driving on the freeway approximately 65-70 mph the rpms are jumping up to 2200-2700 rpms. What could cause that? My husband already checked for vacuum leaks and says he can't find any obvious leaks. We just replaced the map sensor thinking that would fix it but it didn't so I'm thinking it could possibly be a bad Throttle Body w/Actuator IAC Idle Air Control or a TPS Position Sensor or even possibly a upstream 02 sensor. If anyone else can give me some advice on what I should fix next I would greatly appreciate it thank you!

Yeah😅👍🏻👍🏻👍🏻

2014 Chevy impala. Nothing wrong with performance just p0171 code. Checked everything no cracks in hoses, no hoses are unplugged, replaced o2 sensor already. Have no idea.

I probably got one of the worst.. P0332 knock sensor

Is it possible a o2 sensor could be faulty???

Exactly what I needed. No boring stuff. Straight to the point. My highly trusted 06 XB finally came up with this P0171 code and I was trying to figure out why. I did clean the MAF sensor and throttle body a while ago and may have messed up something. Thanks a lot!

Your videos are usually pretty good but you Totally dropped the ball on this one.
The reason for a P0171 is because the oxygen sensor determines the combustion is lean and the fuel trim has to compensate over 25%.
If this happens at idle then it would almost certainly be a vacuum leak after the MAF- particularly if the fuel trim returns to zero under load. However if the fuel trim increase is only under load- it is impossible for it to be a vacuum leak. Either a direct MAF, fuel pressure, compression pressure, or combustion inefficiency is present.
Also there is never a reason to check the airbox on a lean code. Any issue must be AFTER the MAF sensor- never before it.

Hey 1A. Love your videos. I have a question: I broke one of the 10mm bolts when taking the intake off on my ‘05 Cadillac. I just wanna know if there’s a place I can buy just the bolts as opposed to an entire new intake manifold. Thanks for reading

I have this code however there is no vacuum leak, Is there anything else I can do or check? Thanks and love the videos ✌

Nice and simple!

what was the hose that was loose hooked up too ?

Can you do one for running rich code

That helped me bro! Thanks!

Awesome video! I got a code P0171 and P0125
The temperature is reading normal, heater works fine.
It could be a lot of different things. Loss of power going up a steep grade. Put gas in car and the light goes on again. Service station is a dive and the gas was coming out so slow. Glad it's not the CAD though. Will have my son check mass flow thing you mentioned. Bonnie

Thank you

Thanks for the heads up . Same problem with my car . My first car was a 1956 Ford with no sensors and much easier to work on . I only wish they were still made that way .

You should do a video on adding blinker fluid lol!