Code result
P0321
Ignition/Distributor Engine Speed Input Circuit Range/Performance
High severity
What it means
Engine speed input from the ignition/distributor is in electrical range but plausibility check fails — slow response, drift, or noise.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Sensor drift or pickup gap wrong
highOne of the most commonly reported causes for this code — check this first.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Sensor mounting loose - signal damping
lowLess common, but worth ruling out after the more likely causes.
Related help
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