Ignition coil replacement
An ignition coil creates the high voltage for the spark.
Symptoms
- The engine misfires, loses power, and a misfire fault appears on the dash.
What's included
- When it breaks down, its cylinder stops working: the engine misfires and loses power, a misfire fault appears on the dashboard, and in limp mode the control unit may cut fuel to that cylinder. We identify the faulty coil with a cylinder-by-cylinder scan and confirm it by swapping coils: if the misfire moves with the coil, the diagnosis is clear. Failure of one coil does not always require replacing the entire set; we advise based on mileage and the condition of the others. We also check spark plugs and boots, because they often cause the breakdown.
Additional checks
- Cylinder-by-cylinder scan to pinpoint the faulty coil
- Spark plugs and boots — checked at the same time
- Condition of the remaining coils and mileage — to judge whether the full set needs replacing
Why it matters
Swapping the coil and plug confirms the diagnosis: if the misfire moves with the coil, the cause is clear. Replacing the whole set isn't always necessary.
More details
The ignition coil generates the high voltage for the spark. When it breaks down, the cylinder stops firing: the engine misfires, loses power, a misfire fault code appears on the dashboard, and in limp mode the control unit may cut off fuel to that cylinder entirely. We identify the faulty coil per cylinder with the scanner and confirm it by swapping coils — if the misfire "moves" along with the coil, the diagnosis is certain. Replacing the whole set when just one has failed isn't always necessary; we'll advise based on mileage and the condition of the rest. At the same time we check the condition of the spark plugs and boots — a coil often breaks down because of them.
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