I was just stuck in traffic and I was in first or second gear and drving around 5mph. Then I get this "service engine soon" come on. The car didn't jerk or anything. So I pulled the code and it reads P0171. Now I know that means running lean on bank 1. I'm just thinking what could of caused this. I got the greddy 720cc injectors install and tune last month. Now it's never done that the pass 30 days after the tune, so I don't know why its throwing this code now. Do you guys think its the tune? my injectors going bad? any help would be appreciated guys. Thanks

 

Does bad tank of gas do it also?

 

Ive heard of the front o2 going bad, but car is new i doubt thats it. Plus that sensor is a fortune. I also seen a leak on the intake on the turbo throw that code.

Is that the only code your throwing?

Do a PO171 search im sure other people have had the same problem.

 

I had that problem for a long time. It can be caused by MANY things. Leaking exhaust, leaking head gasket, bad O2 sensor, improper scaling on injectors, misfiring cylinder, bad spark plugs....and I'm sure a few other things.

 

maf coudl be dirty too/

 

 

Well it's been 3 days now after I reset the code. The check engine light hasn't come on yet. so I scan it with the OBDII scaner and nothing is pending. I talked to the tuner and he said it happens when part throttle, so nothing to worry about. Well I'm gonna keep an eye on it for the next few days to see if it throws it again. Thanks for all the input.

 

I recently had a custom tune, cossworth cams, fuel pump and 680 injectors installed. The car runs great and all but I keep getting the SES light when I drive slow.

Once the SES light comes on, P0171, the car starts to idle bad. To a point that it feels like it's gonna die.

I guess it's similar to the issue of the original post. What is the fix for this? Is this truely a tuning issue?

TIA.

 

Let's not forget about leaking vacuum lines and such... it can cause the car to run lean also... basically your car is running a bit on the lean side for it to cause that..

 

My tuner is saying it's the part throttle thats running lean. I took it back to him and he dial it out alittle and it hasn't thrown that code since. and that was 4 months ago. I think you should take it back to your tuner and have it retune. Hope that helps