alia176
SILVER Star
I removed the intake hose n looked at it looks good, did a smokers test and no leak I can see, cleaned the MAF last night. Gonna cut the tape on the wiring n inspect it, I will advise what I find,
i like that "smokers" test .
As mentioned previously, your ECU thinks it's running too lean. Meaning either "too much" unmeasured air entering the intake after the MAF sensor. Or, your engine is starving for fuel. Looks like you're on the right track by looking for unmetered/unmeasured (post MAF) air is sneaking into your engine.
Did you check the check valve at the hydro brake vac booster? For that matter, did you check the vac booster to see if it holds vacuum? It's a WAG but might be worth checking.
The myriad of hoses under the intake can get brittle ends. Be sure to replace those PITA hoses or trim the ends. The hoses will feel soft but the ends might be split due to age. Since I run a turbo, I went a little far by applying safety wires to the ends (circled in red) just so they don't pop off after few years.
A P0171 code is set by your vehicle's powertrain control module (PCM) when it detects that the air-to-fuel ratio of your vehicle is too lean. This means that the PCM is relaying that the engine is receiving too much air into the combustion chamber and not enough fuel.