DTC Confirmation Test

WARNING: This page is about a different car, the 2002 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.

Malfunction is detected when mixture ratio compensation amount is too large (mixture is too lean or too rich). Possible causes are:

Intake air leaks.
Defective front HO2S.
Defective injectors.
Exhaust leaks.
Fuel pressure incorrect.
Lack of fuel.
Defective MAF sensor.

To set DTC, start engine and warm to normal operating temperature. Turn ignition off and wait at least 10 seconds. Disconnect MAF sensor harness connector located near air cleaner. Start engine and let it idle for at least 5 seconds. Turn ignition off and reconnect MAF sensor harness connector. Turn ignition on. Using scan tool, ensure first trip DTC P0100 is set. Clear DTCs. Start engine and let it idle for at least 10 minutes. Check for DTCs. If DTC P0171 or DTC P0172 is present, perform DIAGNOSTIC PROCEDURE . If engine was difficult to start, fuel injection system has a malfunction. Attempt to start engine while depressing accelerator pedal. If engine does not start, check for intake or exhaust leaks or spark plug fouling.