PO171 - Air Leak in Fuel Inj. System
Here is some info on the PO171 issue:
ECM-262A LONG-TERM FUEL TRIM
Checking fuel injection system
Check intake system for air leakage according to See: Component Tests\Check For Air Leaks In the Intake System
Hint: Air leakage in the intake system can occur through the canister purge (CP) valve, the secondary air solenoid valve and power brake booster.
Start the engine and idle it for 10 minutes
Check the mass air flow (MAF) sensor by Read its correction factors. The value should be between 2 and 12
NOTE: There must not be any air leakage when this test is carried out.
Remedy as necessary.
To access/replace the Mass Air Flow (MAF) sensor, See: Component Tests\Component Access/Replace Procedures\Mass Air Flow (MAF) Sensor, Replacing
Test drive the car according to the TRIP schedule, See: Monitors, Trips and/or Drive Cycle (Readiness Codes)
Do not turn off engine after test drive.
Connect the car to VADIS again.
Read off fuel trim status.
There should not be any faults when fuel trim is finished.
Was a fault detected?
Yes - Continue below.
No - Testing Complete.
The fault should have been detected and remedied. As this is not the case fault-tracing has failed. Exit fault tracing for this diagnostic trouble code (DTC) or make another attempt.
1999 V70 XC Dark Blue/Taupe - Gas/Auto Trans. with Nokian WRG2s 205/65/15
2002 Acura TL White/Tan