Engine Cranks But Won't Start (Cold Start)
The engine cranks normally but fails to start when cold. This indicates a lack of spark, fuel, or compression, or a sensor issue affecting cold-start enrichment.
Diagnosis Details
Possible Causes
Faulty engine coolant temperature sensor (ECT) causing incorrect fuel mixture
Weak fuel pump or clogged fuel filter (fuel pressure drops overnight)
Crankshaft position sensor or camshaft position sensor failure
Faulty ignition coils or spark plugs (worn or fouled)
Vacuum leak or intake air temperature sensor issue
Related OBD-II Codes
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What You Should Do
Check for diagnostic trouble codes (DTCs) with an OBD-II scanner.
Test fuel pressure, inspect spark plugs and coils, and verify ECT sensor readings with a multimeter or scan tool.
If no codes, perform a no-start diagnostic (spark, fuel, compression).
Related Repairs
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Disclaimer: This AI-generated diagnosis is for informational reference only. Always consult a qualified mechanic for an in-person inspection. AutOwner is not responsible for decisions made based on this information.
