P0321 code meaning
Ignition/Distributor Engine Speed Input Circuit Range/Performance
Powertrain system Generic code P03xx codes Check engine light
What P0321 means
P0321 belongs to the same signal as P0320 and P0322: the speed and reference input of the ignition, formerly the distributor's Hall pickup, today practically always the crankshaft position sensor. Range/Performance means a signal is present but implausible – wrong number of teeth between the reference gaps, erratic tooth times, or a speed that does not fit the camshaft signal. No manufacturer document available to us describes P0321 by code: Ford runs these tooth checks under P0320 or P0339 (wrong tooth count after the gap, tooth time outside 30 to 9,000 rpm, gap at the wrong position) and GM under P0336. The description therefore follows that logic and CARB's rationality requirement for crank angle sensors.
P0321 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0321
- Check engine light on
- Jerking, misfire or brief stalling
- Hard starting, long cranking
- Tachometer flickers or drops out
Common causes of P0321
- Most likelyCrankshaft position sensor faulty or aged (weak, noisy signal)
- PossibleSensor loose or air gap wrong
- PossibleTone wheel damaged or clogged with metal chips
- PossibleInterference, poor ground or damaged wiring
- Less likelyEngine module or software
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Crankshaft position sensorCrankshaft tone wheelSensor wiringEngine control module
What each part of P0321 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 3 | Area: ignition system or misfire. |
| 21 | The exact fault in that area. |
What to do next
- Note P0321 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0321
What does P0321 mean?
P0321 means "Ignition/Distributor Engine Speed Input Circuit Range/Performance". P0321 belongs to the same signal as P0320 and P0322: the speed and reference input of the ignition, formerly the distributor's Hall pickup, today practically always the crankshaft position sensor. It is a generic code, so it means the same on every make.
Is it safe to drive with P0321?
Drive gently and only to a workshop. With P0321 the car can go into limp mode (reduced power) to protect itself.
Will P0321 fail an emissions test?
Yes, it can. P0321 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0321 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0321 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.