P0351
Ignition Coil A Primary Control Circuit/Open
Ignition / coil
Generic OBD-II
High
What it means
P0351 means the ECM has detected an electrical fault — often an open — in the primary control circuit for ignition coil 'A'. Without a working coil, that cylinder misfires, so the engine runs rough and loses power. Because a misfire can damage the catalytic converter, it should be repaired quickly rather than driven on.
High
Can I keep driving? Not for long — a dead coil means a misfiring cylinder, so the engine runs rough and unburned fuel can damage the catalytic converter; drive as little as possible.
Common symptoms
What you'll notice
- Check-engine light on, sometimes flashing during an active misfire
- Engine misfire, rough idle, and shaking
- Reduced power and hesitation on acceleration
- Hard starting in some cases
Common causes
Most likely first
- Faulty ignition coil 'A' or its connectorLikely
- Open, shorted, or damaged wiring in the coil primary control circuitCommon
- Loose or corroded connector at the coilCommon
- Worn spark plug on that cylinder stressing the coilLess often
- Rarely, a faulty ECM coil driverLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and inspect the coil 'A' connector and wiring for damage, corrosion, or an open.
- Check for the coil's power and the ECM control signal at the connector.
- Swap the suspect coil with a known-good one from another cylinder — if the fault follows the coil, replace it.
- Inspect and replace the spark plug on that cylinder if worn.
- Verify the circuit back to the ECM before considering the module; clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0351?+
Only briefly. A dead coil makes the cylinder misfire, and dumping unburned fuel into the exhaust can overheat and ruin the catalytic converter. Fix it promptly.
Can I just clear P0351?+
It comes right back — this is a circuit fault. The coil, wiring, or connector has to be repaired for it to stay off.
Related codes
Often seen with P0351
Read & clear P0351 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