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.

Real-world scan data

Seen in

2,525

scans in the past year

Found in

0.4%

of scans

0.7%

of scans that found faults

Appears alongside · share of P0351 scans

P0352in 52.8% of scans

P0353in 42.9% of scans

P0301in 26.6% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

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.

Read & clear P0351 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX