P0354 Ignition Coil "D" Primary/Secondary Circuit
Fault in the circuit of ignition coil "D" (usually the coil for cylinder 4).
Common causes
- Faulty ignition coil
- Damaged wiring or connector
- Worn spark plug overloading the coil
Symptoms
- Check engine light
- Misfire on the related cylinder
- Rough running
What to check
- Swap the coil and see if the fault moves
- Inspect connector
- Check spark plug condition
Manufacturers may add their own detail to generic codes. If your vehicle shows a different description for P0354, follow the service information for that make and model.