I changed out the coolant level sensor this past weekend and removed the airbox and it dropped on the ground (not a big drop). After getting everything back installed, I got a p0171 code after about 50 miles (had disconnected battery). Replaced all the vacuum lines connect to the airbox thinking that I had messed them up, cleared code and it came back after another 50 miles. Cleaned MAF and cleared code, came back. Noticed that one of the screws holding MAF was stripped and MAF not sealed correctly so used a larger screw and reseated MAF. Idle improved but after about 80 miles the idle blipped again and then code came back.

Tried searching to see how to test MAF but can't find anything. I have a code reader but that's it. Is it likely I just broke the MAF?

 

check the gasket around the MAF.

im not sure if there are screens in the oem airbox, but my second screen closest to my maf turned sideways after a hard pull and my gasket was broken around my maf. It gave me the P0171 engine lean code and when i started it, it would try really hard to stay on for 2 seconds and then just shut off. When i tried to help it out by giving it gas, it backfired like no other.

it happened after i made a trip to rotorfest and was 10min away from the event after driving for 1.5hrs. Straightened out the screens in my intake and used electrical tape around the maf to seal it(obviously poke a hole where the maf sensor goes in the tube)

You said you used a bigger screw?? that may have messed it up, you might have ruined the threads in the intake where the maf gets held in. Or did you buy a replacement screw of the same size?

SORRY FOR THE HUGE PIC!! Just wanted to show you how i fixed the gasket problem until i could get home....

 

Have it here and gasket looks like in good shape and it's seated on the sensor okay. How tight should the fit be? I am pretty sure this one is an aftermarket one.

 

aftermarket intake?? what does it look like, post a picture.

if you are unsure look up pics of....

WeaponR/RacingBeat/Aem/AutoExe/K&N/Injen

just to name a few..

 

Sorry, the MAF is an aftermarket one. The airbox is stock, unfortunately.

 

I replaced the screw (it was stripped) with a slightly larger one and it fits pretty evenly. I was thinking of using gasket maker to try and seal it better but was worried about making a mess.

Will look at the screens but that airbox is a pain to get open. May have to wait until morning.

 

Did you replace the pesky tiny vacuum line under the TB??

Try cleaning the MAF?

other than that i do not know, wait for someone more knowledgeable to post, i havnt read through enough problems and diagnoses to be able to diagnose whats going on to you.

while you are waiting, search "P0171" under the advanced search under "thread titles" and do some reading, it could be a few other things that i am not remembering.

My money is on a vacuum line...

oh... RIWWP had a similar problem except it was the gasket between the UIM... i believe..

 

Cleaned MAF twice. Searched the p0171 and it had a lot of different things but since I just did a repair, I am hoping that I screwed something up in the area where I was working. Will look for that line under the TB.

 

faulty aftermarket MAF maybe? Was everything working before you pulled your airbox? If so then its something you did.

 

Do you know what the line is at the front of the airbox (two metal lines coming from under the airbox with a rubber line in between?

 

Yes, i believe that is for the VFAD.

 

Well, I bought a MAF. We'll see.

 

dont know why nobody has posted here yet.....

 

Haven't driven it enough to complete the emissions cycle. About 60 miles but Evap system still is not ready. Hoping the MAF fixed things.

 

Finally the issue appears to be resolved. Have driven about 120 miles and the emissions system has gone into ready mode. When I first installed the new MAF, the car ran like crap including setting off a p0336 code. I disconnected the battery, did the 20 taps on the brake and everything has been fine since.

Hopefully I haven't jinxed myself.