P0174
[P0174] The scan tool indicates Diagnostic Trouble Code (DTC) P0174: The fuel system is too lean [Front Bank (Bank 2)]
Description
By monitoring the Long Term Fuel Trim, long term malfunctions in the fuel system will be detected.
If a malfunction has been detected in two consecutive trips, the MIL will come on and DTC P0171, P0172, P0174 and/or P0175 will be stored.
NOTE: If some of the DTCs listed below are stored at the same time as DTC P0171, P0172, P0174 and/or P0175, troubleshoot those DTCs first, then troubleshoot DTC P0171, P0172, P0174 and/or P0175.
P0107-8, P1128-9: MAP Sensor
P0135: Rear Primary HO2S Heater (Bank 1, Sensor 1)
P0137-8: Rear Secondary HO2S (Bank 1, Sensor 2)
P0141: Rear Secondary HO2S Heater (Bank 1, Sensor 2)
P0155: Front Primary HO2S Heater (Bank 2, Sensor 1)
P0157-8: Front Secondary HO2S (Bank 2, Sensor 2)
P0161: Front Secondary HO2S Heater (Bank 2, Sensor 2)
P0401: EGR Flow Insufficient
P0441: EVAP System Incorrect Purge Flow
P1259, P1279: VTEC System
P1491: EGR Valve Lift Insufficient
P1498: EGR Valve Lift Sensor High Voltage
Possible Cause
- Fuel Pump not enough flow/pressure
- Fuel Feed Line clogged, leaking
- Fuel Pressure Regulator stuck open
- Fuel Filter clogged
- Fuel Injector clogged, air inclusion
- Gasoline doesn't meet Owner's Manual specification.
- Primary HO2S (Sensor 1) deteriorated
- EGR System not enough flow
- Valve Clearance
- Exhaust leakage