What Is an Ignition Coil?
Ignition coils make the spark that runs your petrol engine. A Cranbourne West specialist explains.
What it is & what it does
An ignition coil transforms the battery’s 12 volts into the tens of thousands of volts a spark plug needs — modern engines use one small “coil-on-plug” per cylinder, fired precisely by the computer.
Heat and vibration age them; worn spark plugs make them work even harder.
Signs of trouble & how we help
A failing coil causes a misfire on its cylinder — stumbling, shaking, a flashing check-engine light — often worse under load or in damp weather. Because plugs and coils age together, worn plugs commonly take coils with them.
We identify the exact failing coil from misfire data rather than replacing a full set on guesswork — though we’ll advise when a set genuinely makes sense.
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Understanding what’s under the bonnet makes servicing decisions easier — and we’re always happy to explain what your car needs and why, in plain English.
Book a service or a check with a Cranbourne West specialist online in 60 seconds, or call 03 8782 0711.
What Is an Ignition Coil? — FAQ
It steps 12V up to the tens of thousands of volts the spark plug needs — one coil per cylinder on modern engines.
A misfire — stumbling, shaking, a flashing check-engine light — often worse under load or damp.
They make coils work much harder — the two age together, which is why plugs on time protect coils.
We identify the failed one from misfire data and advise honestly when a set makes sense.
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