P0351 — Ignition Coil A Primary/Secondary Circuit Malfunction
Drivable short-term, but fix now to avoid damage.
What P0351 means
This code points to a primary or secondary circuit malfunction in ignition coil A, which is typically the coil for cylinder 1. The computer detects an electrical problem in how the coil fires, leading to a misfire that causes rough running, lost power, and potential catalytic converter damage. It's usually fixed by replacing the faulty coil or repairing its wiring and connector.
Common symptoms
- Check engine light is on or flashing
- Misfire felt as engine shaking or vibration
- Loss of power and rough acceleration
- Rough idle or stalling
- Higher fuel consumption
Common causes
- Faulty ignition coil on cylinder 1
- Damaged coil wiring or connector
- Open or shorted primary/secondary circuit
- Worn or fouled spark plug on cylinder 1
- Faulty ignition driver in the engine computer (rare)
Typical repair cost
$100 – $400
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0351 code?
Keep it to a minimum, and stop entirely if the check engine light is flashing. A flashing light means an active misfire that can ruin the catalytic converter, so prompt repair is important.
How much does it cost to fix a P0351 code?
Expect about $100 to $400. Replacing the cylinder 1 coil and spark plug is the typical fix, while wiring repairs can add to the cost.
Is a P0351 code serious?
Yes. A misfire on cylinder 1 can damage the catalytic converter and leave the engine running rough, so it should be repaired without much delay.
Which cylinder does the P0351 code refer to?
Ignition coil A almost always corresponds to cylinder 1. Replacing that coil and checking its spark plug and wiring is the usual starting point for repairs.