P021A
Cylinder 7 Injection Timing
Fuel injection timing
Generic OBD-II
High
What it means
P021A means the engine computer has detected that fuel injection timing on cylinder 7 is incorrect — the injector isn't firing at the right point in the combustion cycle. That makes the cylinder contribute poorly, so the engine runs rough, loses power, and may be hard to start. It's most often tied to the crankshaft or camshaft position signals, or to a fault in that cylinder's injector or wiring.
High
Can I keep driving? Drivable but likely rough — injection timing that's off on a cylinder causes misfire-like running and reduced power; get it checked soon.
Common symptoms
What you'll notice
- Check-engine light on
- Rough running or misfire-like shaking
- Reduced power and hesitation
- Hard starting in some cases
- Increased smoke or fuel use (diesel)
Common causes
Most likely first
- Crank/cam position correlation off, or a faulty crankshaft or camshaft position sensorLikely
- Injector or injection-pump fault on cylinder 7Common
- Damaged wiring in the injection-control circuitCommon
- Failed powertrain control module (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for crank/cam position or other injector codes.
- Inspect the cylinder-7 injector wiring and connector.
- Test the crankshaft and camshaft position sensors and their timing correlation.
- Check the injector and, on diesels, injection-pump timing per the service procedure.
- Suspect the PCM only after sensors, wiring, and injector check out.
FAQ
Quick answers
Is it safe to drive with P021A?+
Brief driving is usually possible, but rough running and reduced power make it a poor idea to keep driving. Persistent mis-timed combustion can strain the engine and converter, so have it diagnosed soon.
Can I just clear P021A?+
It will return once the engine runs, because the timing error on cylinder 7 is still present until the sensor, wiring, or injector cause is fixed.
Related codes
Often seen with P021A
Read & clear P021A 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