Common Symptoms
- Check engine light illuminated
- Engine cranks but will not start
- Intermittent stalling or no-start condition
- Rough idle or engine misfires
- Loss of power or hesitation during acceleration
- Tachometer erratic or not functioning
Most Likely Root Causes
- Faulty crankshaft position sensor
- Damaged or corroded wiring harness to crankshaft position sensor
- Poor electrical connection at crankshaft position sensor connector
- Short to voltage in crankshaft position sensor circuit
- Faulty engine control module
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Component Location
The crankshaft position sensor is typically mounted near the crankshaft pulley, harmonic balancer, or on the engine block near the flywheel or flexplate.
Manufacturer Notes
Some manufacturers use magnetic or Hall-effect type crankshaft position sensors which have different voltage characteristics and failure modes.
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