
1999 Ford F-150 Lariat 5.4L Poor Idle Quality, MIL Lamp on
Check engine light is on for bank 1 only running lean. Bank 2 is not indicated as too lean but LTFT is 19, LTFT on B1 is 25+. No vacuum leaks found. It seems only when vehicle engine cold the problem occurs. At warm idle, the STFT are always 0 +/- 3%. Odometer...
FIX posted 8/28/2013
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Message Closed w/FIX
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VIN | 1FTRX18LXX |
Engine | 5.4 L / 8 cyl / GAS |
Trans | 4-speed Automatic (Electronic) |
Delivery | Fuel Injection |
Emissions | OBD-II Compliant |
Symptoms | Poor Idle Quality, MIL Lamp On |
Occurs | Cold |
Trouble Codes
P0171 | Fuel System Too Lean (Bank 1) |
P1815 | TFP Valve Position Switch - Start In Wrong Range |
U1262 | Data Circuit Malfunction |
Message Closed w/FIX
Vehicle Data
1999 Ford F-150 Lariat
VIN | 1FTRX18LXX |
Engine | 5.4 L / 8 cyl / GAS |
Trans | 4-speed Automatic (Electronic) |
Delivery | Fuel Injection |
Emissions | OBD-II Compliant |
Symptoms | Poor Idle Quality, MIL Lamp On |
Occurs | Cold |
Trouble Codes
P0171 | Fuel System Too Lean (Bank 1) |
P1815 | TFP Valve Position Switch - Start In Wrong Range |
U1262 | Data Circuit Malfunction |