I've had the P0171 code before on my 2006 Vibe. The first time, the O2 sensor was replaced. A couple of months later, the CEL came on again, and this time (different mechanic), I was told it was probably just the MAF sensor needing cleaning. They did so, and everything was fine for several months. It came on again about 3 months ago. This time I cleaned the MAF sensor myself, using a can of MAF sensor cleaner. Now, about a week ago, the CEL came on again. I had Autozone pull the code, and it's P0171 again. I can clean the MAF sensor again, but I'm thinking there must be something else going on, the sensor should be pretty dang clean by this point. Ideas?Thanks,Harry
My '06 throws this code every couple of months. Usually after a long drive at sustained highway speeds (60-70mph). When I reset it with my code reader it does not come again for a month or two. I have a Cosmo CAI and Magnaflow exhaust which I thought may have an effect on the situation. Try using a bottle of Techron fuel system cleaner, it has worked magic for me in the past.
[QUOTE=j1yuan]P0171 shouldn't be caused by O2 sensor according to this web page at RepairPal.com --> http://repairpal.com/OBD-II-Code-P0171-and-P0174That's pretty much what the repair guy told me. Since I've cleaned the MAF sensor three times now, is it time to consider replacing it? How do you know when it's actually gone bad? I'm at about 70,000 miles, BTW.
Quote, originally posted by harryb »Since I've cleaned the MAF sensor three times now,When you cleaned it, was the MAF sensor dirty? If it was, why? You have to prevent it from becoming dirty. In my case, the problem was caused by the air cleaner casing which wasn't closed properly (by the previous owner). Once I close it properly, the MAF sensor never becomes dirty again.
Have similar problem... 2006 Pontiac... Cleaned sensor few times, CE come back, Was recall for change PCM, CE come back... Today checked L-shape hose attached to the intake big rubber hose and viola! It comes out easy, so it was not installed properly on the beginning... Before I may see the shoulder of the small hose, after I pressed it firmly down the shoulder stopped by flange of the hole of the big rubber intake hose making better seal. I believe this was original problem!