Diagnostic Trouble Code (DTC) Information ECM-250A

Condition 

Engine Control Module (ECM) receives information from the heated oxygen sensor about fuel/air mixture in different load areas. If Engine Control Module (ECM) registers that fuel/air mixture deviates too much from target lambda, so that adaptations end up in any of its end-positions, the diagnostic trouble code is generated.

Substitute Value 

• None.

Possible Source 

Upper limit 

• Incorrectly installed oil dipstick. Air leakage.
• Too high ethanol content in fuel.
• Air leakage in the intake system.
• Air leakage in the exhaust system.
• Low fuel pressure.
• Damaged mass air flow (MAF) sensor.
• Damaged, dirty oil trap.

Lower limit 

• Oil level too high.
• Contaminated engine oil.
• Leaking injectors.
• Damaged evaporative emission system (EVAP) valve.
• High fuel pressure.
• Damaged mass air flow (MAF) sensor.
• Damaged, dirty oil trap.

Fault symptom[s] 

• Warning lights and chimes/Malfunction Indicator Light ("Check engine" light) indication/no indication
• Text window and warning symbol/Yellow symbol and text message
• Driving/Poor performance/lacks power
• Fuel system/Excessive fuel consumption