Ignition Coil Failure: Signs and Diagnosis
By a Master Tech with 15+ Years Under the Hood Quick Answer: A failing ignition coil causes rough idle, misfires, poor fuel economy, and a flashing check-engine light. Swap the suspect coil to a different cylinder—if the misfire follows the coil, you’ve found the culprit. Expect $80-$180 for a single OEM coil versus $400-$700 at … Read more