P0357

The P0357 code means the PCM has detected a fault in the primary or secondary circuit of Ignition Coil G, which controls cylinder 7. This code only applies to engines with 7 or more cylinders — primarily V8, V10, and V12 configurations. On most domestic V8 engines, cylinder 7 is located on the driver's side (Bank 2) near the rear of the engine.

V8 engines have more ignition coils and spark plugs to maintain, and the rear cylinders are often harder to access. On many truck and SUV V8 engines, reaching cylinder 7 may require removing air intake components or working from underneath. Despite the access challenges, the repair itself is straightforward once you can reach the coil.

If this code appears on a high-mileage V8 (over 80,000-100,000 miles), consider replacing all eight coils and spark plugs as a set. Coils on V8 engines tend to fail in sequence — fixing one today often means another fails next month. Doing them all at once saves the repeated diagnostic fees and the hassle of accessing the rear cylinders multiple times. A complete set of eight coils and plugs typically runs $200-$400 in parts for most domestic V8s.

Severity

Symptoms

• •Engine misfires on cylinder 7
• •Check Engine light is on (may flash)
• •Rough idle with noticeable vibration
• •Significant loss of power
• •Fuel smell from exhaust
• •Reduced fuel economy

Likely Causes

Estimated Cost

Common Fixes

1. Replace the ignition coil for cylinder 7
2. Replace the spark plug for cylinder 7
3. Repair or replace damaged wiring and connectors
4. Swap the coil with another cylinder to isolate the problem

Shop Parts

Related Codes