Dtc p0171

Need help has a 97 PA with code P0171 I have replace both O2 sensors,MAF,Idle control,Check for vacuum leak, and also replace fuild filter but code still show up every morning i start the car i let it warm up and every time the code pop on, I would value any input i can get right now.

I had the same DTC 0171 with my 1997 Ultra. Replaced MAF sensor fuel filter and did the other tests in the GM manual. Turns out the aftermarket MAF sensor I installed was defective. I replaced it and the light has not been on again for 3 months.

A code P0171 may mean that one or more of the following has happened:

The MAF (Mass Air Flow) Sensor is dirty or faulty
Note: The use of "oiled" air filters may cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicleswhere the MAF sensors leak the silicone potting material used to protect the circuitry.
There could be a vacuum leak downstream of the MAF sensor
Possible cracked vacuum or PCV line/connection
Faulty or stuck open PCV valve
Failed or faulty oxygen sensor (bank 1, sensor 1)
Sticking/plugged or failed fuel injector
Low fuel pressure (possible plugged/dirty fuel filter!)
Exhaust leak between engine and first oxygen sensor

check everything on your list I haven't check for exhaust leak yet will take to muffle shop have it check thank alot for the infor,

I found a leak on my 94 PAU between the EGR and the intake. i have a flexible pipe that had small cracks at the flange underneath the mounting hardware for this pipe. i had cracks on both ends.

be advised that this part number GM#24504158 is discontinued. i ended up using JB weld to repair these cracks. seems to be working fine. no more P0171 code.

if you happen to remove this to check for the leak i am talking about. the flexible pipe is flexible, but be careful as you can cause these cracks i talk about by just removing it. the pipe inserts slightly into each location (one side more than the other) and care must be taken not to damage it.

Gary

Thanks Gary for your reply I had a hold in my flex pipe got one off on ebay , but the code still popping up. Don"t know what to try next I"m goinh to change spark plug next see do thet help. Thank again

OK, you are at the point where you need a scan tool on this vehicle, especially reading data when the MAF is disconnected.......and also while spraying the engine, to check O2 data.....