2018 Honda P0351: What It Means & Is It Safe to Drive?
P0351 on the 2018 Honda: Ignition Coil A Primary/Secondary Circuit Malfunction. Here's what it means, what usually causes it, what repairs typically cost, and whether it's safe to keep driving.
What this code means
The PCM detected a fault in the primary or secondary circuit of ignition coil A (cylinder 1 coil on most coil-on-plug systems). This will cause a misfire on the affected cylinder and can damage the catalytic converter if left unresolved.
Common causes on the 2018 Honda
- Failed ignition coil
- Fouled or worn spark plug on that cylinder
- Damaged ignition coil wiring or connector
- Faulty PCM output driver (rare)
Symptoms
- Check Engine Light on, often flashing
- Rough idle and misfire
- Loss of power
- Poor fuel economy
Typical fixes
- Replace ignition coil for cylinder 1
- Replace spark plug on affected cylinder
- Inspect coil wiring and connector
Repair cost range
For a 2018 Honda, repairs for P0351 typically fall between $80 and $300, depending on the root cause and labor rates in your area.
Known issues on Honda
Honda P0351 is most often a failed individual coil. If the coil swap to another cylinder does not move the misfire, inspect the wiring connector and the spark plug. Honda K-series coils are inexpensive and widely available.
Most commonly affected models