Hi,
Can't do a search so have to ask. Am getting the SES light and decoded P0171 and P0174, fuel injection system function (lean) Bank 1 and Bank 2. Have looked at the Service Manual and problem could be an intake air leak after the MAF, Front heated oxygen sensor, injectors, exhaust gas leaks, incorrect fuel pressure, lack of fuel, mass air flow sensor. Possibility of 7 problems, does anyone here know if this (P0171/P0174) code is a common one, and what the problem actually is? I am thinking one or more of the injectors is dirty because occasionally I feel the power drop off slightly while driving at highway speeds or accellerating. I do not have any mods to the engine.

Dannodotcom

 

I had the same problem some time back and i replaced the MAF and everything has been great. I got it from Dave B I believe it was $89 shipped.

 

1) Did you recently change/upgrade anything on your car, especially the intake or exhaust?

2) Check for air leaks, as that's the "cheapest" method. Then start diagnosing the problem using the steps found in the ESM.

 

Unlikely it's injectors or 02s, since it's on BOTH banks. If it was the MAF, you'd probably have more symptoms.

My guess if fuel pressure maybe from a clogged filter or dying fuel pump. IF you check everything else, a $35 fuel pressure gauge from Checker and an hour to eliminate that as a possibility.

 

I'm pretty sure you have this backwards. MAF would cause both banks to be lean because it monitors all incoming air. Most of the time Injectors will only go bad one or two at a time.

 

You are quite the necrotic pervert, sir.