P021D
Cylinder 10 Injection Timing
Fuel injection timing
Generic OBD-II
High
What it means
P021D means the fuel-injection timing for cylinder 10 is outside the expected window — the injection event is happening too early or too late (most relevant on direct-injection and diesel engines). The result is rough running, a possible misfire on that cylinder, reduced power, and harder starting. The cause is usually the injector, its wiring, or a crank/cam timing-reference signal.
High
Can I keep driving? Drivable but may run rough, lack power, or start hard as cylinder 10 misfires; repair soon to avoid a persistent misfire.
Common symptoms
What you'll notice
- Check-engine light on
- Rough running or misfire
- Reduced power and hesitation
- Harder starting
Common causes
Most likely first
- Faulty cylinder 10 injector or its injection-timing controlLikely
- Wiring fault in the fuel-injection control circuitCommon
- Crankshaft or camshaft position sensor error affecting injection timingCommon
- Less commonly, a powertrain control module (PCM) faultLess often
How to diagnose & fix
Work through it in order
- Scan and read freeze-frame data to confirm the cylinder 10 injection-timing fault.
- Inspect the injector and injection-control wiring for damage or a poor connection.
- Check the crankshaft and camshaft position sensor signals, since they set injection timing.
- Test the cylinder 10 injector and replace it if faulty, then clear and retest.
FAQ
Quick answers
Is it safe to drive with P021D?+
Only briefly. Incorrect injection timing on cylinder 10 causes a misfire and power loss and can strain the engine. Repair it soon.
Can I just clear P021D?+
It returns until the injector, wiring, or timing-reference fault is fixed. Because it affects combustion, diagnose the cause rather than clearing it.
Related codes
Often seen with P021D
Read & clear P021D yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX