TorqueMech OBD Code Guide
P0321 - Ignition/Distributor Engine Speed Input Circuit Range/Performance
Engine speed input signal is erratic or out of range.
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Code Overview
Engine speed input signal is erratic or out of range.
Common Causes
- Crank/cam signal issue
- Ignition module fault
- Wiring problem
- Reluctor damage
Diagnostic Steps
- Watch RPM signal during crank and stall events
- Inspect crank and cam sensor connectors
- Check for rubbed-through wiring near the engine
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