1164
UnclassifiedFuel
What This Code Means
Malfunction Indicator Lamp (MIL) ON; Engine operating rich (excess fuel); Adaptive multiplier out of range greater than -30% while running on natural gas; Adaptive Learn function disabled for the key cycle; One bank shows high adaptive and the other is low; MIL ON; System runs rich
Possible Causes
- •High fuel supply pressure (secondary fuel pressure)
- •Worn fuel mixer
- •Faulty EPR (Electronic Pressure Regulator)
- •Drastic variation in fuel quality (very high butane content)
- •Plugged, damaged, or modified air filter
- •Crossed O2 sensor leads
- •Faulty or mispositioned oxygen sensor (HEGO/UEGO) providing incorrect air-fuel ratio data
- •Oxygen sensor wire shorted to ground or damaged in the harness
- •Excessive fuel pressure caused by a failing gaseous control actuator, valve, or regulator
- •Faulty pressure control system unable to regulate fuel delivery under varying engine loads
- •Engines operating on wellhead gas or other non-standard fuels with high inert gas content or inconsistent energy density
- •Adaptive multiplier out of range greater than -30% while running on natural gas
- •High secondary fuel pressure
- •Plugged, damaged or modified air filter
Suggested Actions
- 1Ensure specified HD-5 or HD-10 fuel grade propane is used
- 2Trace crossed O2 sensor wires back to their ECM and correct accordingly
- 3Run the fuel system diagnostics
- 4Trace O2 sensor wires back to their ECMs and correct crossed leads
Related Power Solutions International Fault Codes
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