DTC 1153
UnclassifiedEmissions
What This Code Means
MIL ON; False lean condition; Closed Loop multiplier out of range (greater than 35%) while running on natural gas; Lean exhaust condition; Misfire (cylinder passing oxygen through without burning); One engine bank shows high adaptive multiplier and the other shows low
Possible Causes
- •Low fuel pressure
- •Faulty fuel mixer
- •Large vacuum leaks
- •Crankcase leaks
- •Faulty EPR (Electronic Pressure Regulator)
- •Exhaust leak pulling outside air past the O2 sensor
- •Drastic variation in fuel quality
- •Faulty grounds causing high resistance between ECM/engine and battery
- •Oxygen sensor wire mispositioned and contacting the exhaust
- •Short to ground between harness and sensor sense signal
- •Crossed O2 sensor leads
Suggested Actions
- 1Ensure fuel pressure is not too low
- 2Ensure gaseous fuel control actuator/regulator has proper fuel pressure under all operating conditions
- 3Check for short to ground between harness and sensor sense signal
- 4Ensure ECM and engine are grounded to the battery with very little resistance
- 5Replace the O2 sensors with known good parts and retest
- 6Correct O2 sensor leads if they are crossed
Related Power Solutions International Fault Codes
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