Common Symptoms
- Engine cranks but fails to start intermittently
- Engine stalls randomly while driving
- Rough idle or hesitation during acceleration
- Check Engine Light illuminated
- Intermittent no-start condition especially when engine is hot or cold
Most Likely Root Causes
- Damaged or worn crankshaft position sensor
- Corroded or loose sensor connector
- Damaged sensor wiring harness or chafing against engine components
- Reluctor ring or tone wheel damage or debris buildup
- Poor electrical ground connection at sensor or ECM
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Component Location
The crankshaft position sensor is typically mounted on the engine block or timing cover near the crankshaft pulley or flywheel.
Manufacturer Notes
Some manufacturers use magnetic or Hall-effect type crankshaft sensors which have different failure modes and diagnostic approaches.
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