P0171

[mixxer]

hi new to the forum ive read alot but have never posted i have an issue with

P0171 (freeze frame) also p0174 (generic code)

fuel system 1 CL
calc load(%)52.55
ect 85
stft b1 % -3.91
ltft b1 % 1.56
stft b2 % -3.13
ltft b2% 3.13
eng rpm 2243
veh speed km/h 46

anyone know what all this means?
have changed fuel filter , plugs and wires , cleaned MAF idle is same warm and cold and i have sprayed carb cleaner by my intake gaskets and no change in idol havent found a air leak just yet as i dont know my way around this truck all that great but i been trying
thanks much

 

[Gus Gorilla]

P0171 = Lean on bank 1
P0174 = Lean on bank 2.
This data came from a freeze frame event. Your truck saw a failure event and saved it for just such an occasion.
Going down the list of data provided...
Engine load %52.55
Engine Coolant Temp 85
stft b1 = Short Term Fuel Trim Bank 1
ltft b1 = Long Term Fuel Trim Bank 1
The fuel trims are powertrain adaptive strategies for how to manage fuel delivery. Both of your short term fuel trims are pretty far from what your engine usually runs, (long term fuel trims) something suddenly caused that. Since it's running lean suspect a vacuum leak. I had the same thing on my '01 ST which is the same 4.0 engine. There is a line running front to rear, on top of the engine, on the passenger side, that is known to fail. It hooks back around the intake manifold at the rear of the engine compartment. Check that line at the rubber elbows, that's where mine failed. Good luck to you and post back with results.

 

[mixxer]

ive checked all hoses cant seem to find the leak
sounds like an air leak used alot of carb cleaner spraying around but unable to find the leak there is a 3 way right behind the motor that i can not see but i can feel it it doesn't seem to have any knick or breaks though but it is possible that i missed it

raining outside today so i didn't have much time before i came in

could not find the elbow you speak of though

 

[Gus Gorilla]

It may have been the T, It's been a few years since mine acted up and I haven't been out to check it in the last few days. I would thing you could have found it with the carb cleaner but it depends on when you tried it. Your truck faulted with ECT at 85 degrees. As they say in NASCAR "you didn't even get your water warm" You should be sure to try it on the engine when it has sat overnight, cold soak.