Hi Scotty,
I'm new to car repair and watching your videos led me to buy a scan tool. Which I used immediately to my car 2004 Volvo S40 T4. Below are the readings at idle. I plugin the scan tool and just turn on the car but did not start the engine. Are below details and the output for MAF sensor normal?
Freeze Frame
STFT - Bank 1 : -1.6%
LTFT - Bank 1 : 13.3%
Intake Manifold Absolute Pressure: 83.0kPa
Engine RPM : 1693/min
Vehicle Speed: 30km/h
DataStream
LTFT - Bank 1 : 14.1%
STFT - Bank 1 : 0.0%
Intake Manifold Absolute Pressure: 95.0kPa
Engine RPM : 0/min
Vehicle Speed : 0km/h
Ignition Timing Advance for 1 Cylinder : 4.5
Intake Air Temperature : 24 degree celsius
Air Flow Rate from MAF Sensor : 0.00g/s
Absolute Throttle Position : 20.0%
Oxygen Sensor Output Voltage (B1-S1): 0.415V
STFT (B1-S1) : 0.0%
Oxygen Sensor Output Voltage (B1-S2) : 0.420V
STFT (B1-S2) : ---
Thanks for your help
More power to you!
The P0171 code means that, on the first bank of the engine, the fuel system is running weak or a vacuum leak exists near this side of the engine. A lean condition occurs when the engine either receives too little fuel or too much air
On the internet should investigate all the possibilities from easy to hard that would cause a P0171 fault. Easiest is a simple vacuum leak which dilutes the air/fuel mixture causing readings to go out of spec.
