C1540
InfoCooling
What This Code Means
Reduced reliability; Degraded power quality; Misfiring; Rough idle; Check engine lamp; Elevated emissions; Rich or lean condition; Unstable idle; Poor transient response; Intermittent misfiring; No-start condition; Fault code; Elevated exhaust backpressure; Reduced power output; Emissions exceedance; Loss of power; Excessive exhaust smoke; High exhaust temperature; Impacted reliability; Impacted power quality
Possible Causes
- •Deviation from specification in engine tuning, air-fuel calibration, or gas pressure regulation
- •Spark plugs (multi-cylinder) failure
- •Gas regulator / air-fuel mixer failure
- •Ignition system (coils / module) failure
- •Catalytic converter failure
- •Turbocharger failure
Suggested Actions
- 1Verify turbocharger boost pressure
- 2Verify exhaust backpressure
- 3Verify dynamic gas inlet pressure
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