Possible Causes
- Engine compression low.
- Exhaust system leak.
- Front HO2S deterioration.
- Front HO2S heater malfunction.
- Fuel filter clogged or restricted.
- Fuel leakage on fuel line between fuel delivery pipe and fuel pump.
- Fuel pump malfunction.
- Fuel return hose clogged.
- Misfire.
- Pressure regulator malfunction.
- Purge solenoid valve malfunction.
- Purge solenoid valve hoses improperly connected.