The crank signal is irregular or does not fit what the computer expects. The driver may notice misfires, hesitation or stalling.
Causes vary by car. Test before you order a part.
Likely causes, most common first
- Damaged reluctor ring
- Faulty crankshaft sensor
- Poor wiring contact
- Wrong sensor air gap
Parts usually involved
- Crankshaft position sensor Find at suppliers
- Reluctor ring Find at suppliers
- Sensor connector Find at suppliers
Test before you replace
Look at the crank signal on an oscilloscope and inspect the reluctor ring and sensor gap.
General guidance for generic OBD2 codes. Always follow the maker's procedure for the car in front of you.