06/01/2026
Crankshaft Position Sensor - Quick Guide
Core Job: Tells the engine computer (ECU) where the crankshaft is and how fast it's spinning. Without it, your engine won't start or run.
How it works:
· Magnetic type: Creates electrical pulses as teeth on the crankshaft pass by (most common)
· Hall effect type: Sends digital on/off signals (more precise)
· Counts missing teeth on a wheel to find Top Dead Center (starting point)
Location: Usually near front pulley or flywheel
When it fails:
· ❌ Engine cranks but won't start (most common symptom)
· ❌ Intermittent stalling
· ❌ Rough idle, hesitation
· ❌ Check Engine Light (codes P0335-P0339)
Why it matters: It's the primary timing reference for spark plugs and fuel injectors - like the conductor of an orchestra keeping everything in sync.
Quick test: If engine won't start and has no spark/no injector pulse, suspect the crankshaft sensor first.
