P020A
Cylinder 1 Injection Timing
Fuel injection
Generic OBD-II
High
What it means
P020A means the ECM has detected that fuel injection timing for cylinder 1 is incorrect — fuel is being delivered too early or too late relative to the piston's position. Common causes are the cylinder 1 injector itself or the camshaft/crankshaft position signals the ECM uses to time injection. Because combustion is affected, the engine can run rough, knock, and lose power.
High
Can I keep driving? Driveable but likely rough — incorrect injection timing on a cylinder can cause knock, power loss, and rough running, so don't put off the repair.
Common symptoms
What you'll notice
- Check-engine light on
- Rough running or knock/diesel-knock noise
- Reduced power
- Hard starting or rough idle
- Increased emissions or smoke (diesel)
Common causes
Most likely first
- Faulty cylinder 1 fuel injector or its responseLikely
- Faulty camshaft position sensorCommon
- Faulty crankshaft position sensorCommon
- Damaged wiring in the injector control circuitLess often
- Faulty ECM/PCM (rare — rule out injector and sensors first)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for injector-specific and cam/crank position codes.
- Inspect the cylinder 1 injector wiring and connector for damage.
- Test the cylinder 1 injector — resistance, balance, and response against spec.
- Verify camshaft-to-crankshaft correlation and base timing.
- Replace the injector if it fails testing; address any sensor faults. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P020A?+
Keep it short. Wrong injection timing can cause knock and rough running that stresses the engine, so get it diagnosed soon.
Can I just clear P020A?+
It returns until the underlying injector or timing-signal fault is repaired.
Related codes
Often seen with P020A
Read & clear P020A 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