P0357 Code: Ignition Coil G Primary/Secondary Circuit Malfunction
🟠 Moderate severity · drivable
Drivable short-term, but cylinder 7 will misfire and raw fuel can damage the catalytic converter. Stop if the light flashes.
What P0357 means
There's an electrical fault in the ignition coil circuit for cylinder 7 (coil G). The computer can't command that coil, so cylinder 7 loses spark and misfires — P0357 often shows up together with a P0307 cylinder 7 misfire for this reason.
Symptoms
- Check engine light on (may flash)
- Misfire or rough idle on cylinder 7
- Loss of power
- Poor fuel economy
Common causes
- most common: Faulty ignition coil on cylinder 7 (coil G)
- common: Damaged wiring or a loose connector at the coil
- less common: Ignition driver failure inside the engine computer (PCM)
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Swap the cylinder 7 coil with another cylinder to see if the misfire follows it | Yes | $0–20 |
| Replace the cylinder 7 ignition coil | Yes | $50–200 |
| Repair damaged coil wiring or connector | Mechanic | $50–150 |
Frequently asked questions
Which cylinder is coil G?
Coil G fires cylinder 7. P0357 is the cylinder 7 coil circuit.
How do I confirm a bad coil on P0357?
Swap the cylinder 7 coil with another cylinder and re-scan. If the misfire moves, the coil is the culprit.
Does P0357 cause a misfire?
Yes — without spark on cylinder 7, you get a misfire, so P0357 and P0307 often occur together.
Related codes
P0307
P0307 Code: Cylinder 7 Misfire Detected
P0350P0350 Code: Ignition Coil Primary/Secondary Circuit Malfunction
P0356P0356 Code: Ignition Coil F Primary/Secondary Circuit Malfunction
Related guide: The 10 Most Common Check Engine Codes →
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.