Is it a Zetec engine?
P0171 - System too Lean (Bank 1) The Adaptive Fuel Strategy continuously monitors fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit.
Air Measurement System
- MAF sensor (contaminated, damaged, malfunctioning, etc.)
Fuel System
- Fuel pressure regulator (leaking, malfunctioning, etc.).
- Fuel filter plugged, dirty.
- Fuel pump (weak, check valve leaking, etc.).
- Leaking/contaminated fuel injectors.
- Low fuel pressure or running out of fuel.
- EVAP canister purge valve leaking (when canister is "clean").
- Fuel supply line restricted.
- Fuel rail pressure sensor (incorrect reading).
Air Induction System
- Air leaks after the MAF.
- Vacuum Leaks.
- PCV system (leak, valve stuck open, etc.)
- Improperly seated engine oil dipstick.
Exhaust System
- Exhaust leaks before or near the HO2Ss (exhaust manifold gasket, mating gaskets, etc.)..
EGR System
- EGR valve tube/gasket leak
- EVR solenoid vacuum leak
Secondary Air Injection
- Damaged/malfunctioning secondary air injection system (mechanically stuck valve).
View Freeze Frame Data to determine operating conditions when DTC was set. Observe LONGFT1 and 2 PID(s).
P0181 - Engine Fuel Temperature Sensor A Circuit Range/ Performance (EFT) The comprehensive component monitor (CCM) monitors the EFT Temperature for acceptable operating temperature. If during testing voltage were to fall below or exceed a calibrated limit, a calibrated amount of time the test will fail.
- Open or short in harness.
- Low ambient temperature operation.
- Improper harness connection.
- Damaged EFT sensor.
- Damaged PCM.
Verify EFT-PID value to determine open or short
Good luck. This is what I came up with.
Last edited by Tony2005; 05/15/06 12:56 AM.
