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    Warning lights on a car dashboard

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    Why your check engine light is on

    It's always a concern when your car's engine light comes on unexpectedly. Here are some common reasons why.

    Published Dec 2024

    1 min read

    Text size

    Published Dec 2024

    Text size

    Replace your vehicle’s oxygen sensor(s)

    This sensor determines the level of oxygen in the exhaust to assist the engine to run at maximum efficiency.

    Replace catalytic converter(s) with new OE catalytic converter(s)

    This warning is usually seen in older vehicles that have not kept up with regular servicing.

    Inspect for loose fuel cap and tighten or replace as necessary

    Even a loose fuel cap can trigger the engine light. If this is the case, the fuel cap may need to be tightened or replaced.

    Replace ignition coil(s) and spark plug(s)

    These two problems go hand in hand. If a problem occurs with the ignition coil, this can then have an effect on the spark plugs.

    Replace thermostat

    This can be a common problem in high heat regions as the thermostat is a hard-working component within a car’s engine.

    28 August, 2015

    Call us for some peace of mind.

    If a car engine warning light appears, check with RAC first. Call Roadside Assistance on 13 11 11 or make a booking for a free 30 minute car fault diagnosis at one of our nine metro Auto Service Centres.

    Find out more

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