Drive minimally — misfire can damage the catalytic converter. P0353 means the ECM didn't get a proper ignition confirmation from ignition coil “C” — typically cylinder 3. Like the other coil-circuit codes it points to a coil, spark plug, wiring, or ignition-driver fault on that cylinder.
What P0353 means
With coil-on-plug ignition each cylinder has a dedicated coil the ECM fires via an IGT signal, and the igniter returns an IGF confirmation. P0353 sets when the primary/secondary circuit for coil “C” doesn't respond as expected. On most inline engines coil “C” is cylinder 3. It frequently appears with a cylinder-3 misfire code such as P0303.
Symptoms
- Check engine light on, sometimes flashing
- Rough idle and misfire
- Power loss under acceleration
- Hard starting
- Unburned-fuel smell from the exhaust
- Reduced fuel economy
Common causes
- Failed ignition coil on cylinder 3
- Damaged coil connector or wiring
- Worn or fouled spark plug
- Poor power or ground to the coil
- ECM ignition driver fault (rare)
Severity & driving advice
Severity: Moderate — A misfiring cylinder pushes raw fuel into the exhaust and can overheat and destroy the catalytic converter, so fix it promptly.
Can I drive? Drive minimally — misfire can damage the catalytic converter.
Diagnostic approach
- Swap the coil to another cylinder — If the misfire or fault follows the coil, it's bad; if it stays put, look at wiring, the plug, or the ECM.
- Inspect connector and wiring — Check for corrosion, heat damage, or chafing on coil D's circuit.
- Confirm coil power and ground — Verify battery voltage and a solid ground at the coil with the key on.
- Measure coil resistance — Compare primary and secondary windings to spec to confirm an internal coil failure.
- Check the spark plug — Inspect and, if worn, replace the cylinder-3 plug, since a bad plug stresses the coil.
- Test the ECM driver last — Suspect the ECM ignition circuit only after coil, plug, and wiring check out.
Make & model notes
Toyota / general DIS: Each cylinder uses one coil and the igniter returns an IGF confirmation per firing; check coil winding resistance and coil power-source voltage as the standard tests.
General: Coil “C” is cylinder 3 on typical inline engines. Replace or inspect the spark plug with the coil.
FAQ
Which cylinder is coil C?
On most inline engines coil “C” is cylinder number 3. Confirm with your engine's cylinder layout.
Can I test P0353 by swapping coils?
Yes. Move the suspect coil to a different cylinder; if the fault follows, the coil is bad.
Is P0353 safe to keep driving?
Only briefly. The engine runs rough and a persistent misfire can damage the catalytic converter.
Do I need to replace the spark plug too?
It's good practice — a worn plug increases coil load, so inspect and replace it if needed when servicing the coil.