Why Is My Car Using Too Much Fuel?
A sudden drop in fuel economy usually has a fixable cause. A Cranbourne West specialist runs through the common reasons your car is drinking more than it should.
Servicing and sensor causes
Overdue servicing is a big one — old spark plugs, a dirty air filter, or tired oil all hurt economy. So do faulty sensors (like the oxygen or air-flow sensor) that make the engine run rich, often with a check-engine light.
These are common and usually cheap to put right once identified.
Tyres, brakes and driving
Under-inflated tyres, dragging brakes (a sticking caliper), or wheel-alignment issues all add rolling resistance and fuel use. Driving style, short trips and lots of idling matter too — and on diesels, a partially blocked DPF in constant regen will drink fuel.
A quick check often finds an easy win.
Finding the cause
Because the causes range from a tyre pump-up to a sensor fault, a proper check — including reading any fault codes — is the fast way to find where your fuel is going.
Noticed your economy drop? Book a check and we’ll find the cause.
Why Is My Car Using Too Much Fuel? — FAQ
Common causes: overdue servicing (plugs, air filter), faulty sensors running it rich, under-inflated tyres, dragging brakes, or alignment issues.
Often yes — fresh plugs, a clean air filter and correct oil all help, and we can spot sensor faults that waste fuel.
Yes — under-inflated tyres and dragging brakes add resistance and fuel use. Both are quick to check.
We inspect the common items and read fault codes to pinpoint anything making the engine run inefficiently.
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Economy dropped?
Trusted Cranbourne West car specialists — RACV-accredited, fixed written pricing. Book online or call 03 8782 0711.