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Engine

What is an Oil Filter?

Keeps your engine oil clean so internal parts don't wear out.

SPIN-ON OIL FILTER (CUTAWAY)ENGINEOIL PUMP→ to filter← from filterbase plateanti-drain-back valvecenter tubebypass valveOIL FILTERdirty inclean outOil enters round the edge → forced through pleated paper → grit trapped→ clean oil exits the centre

Simplified animation — not to scale.

In plain English

A small canister that filters the oil circulating through your engine, trapping metal shavings, soot, and grit before they can damage moving parts.

A simple analogy

"Like a coffee filter — keeps the grounds out so only the good stuff gets through."

How it works

The oil pump pushes oil through pleated paper inside the filter. Clean oil comes out the other side and lubricates the engine.

Signs of trouble

  • ⚠Oil warning light
  • ⚠Engine noise (knocking or ticking)
  • ⚠Dark, gritty oil on the dipstick
  • ⚠Overdue service interval
Rough UK cost

£10 – £25 (always changed with an oil service)

Always get a written quote. Prices vary by car, region, and parts brand.

Heads up: Carautonomy is for general guidance only. If your car is showing warning lights or behaving oddly, get it looked at by a qualified mechanic.

Keep exploring

Alternator
The on-board power station that keeps your battery topped up.
EGR Valve
A small valve that recycles exhaust gas to reduce emissions.
Starter Motor
The muscle that turns your engine over when you twist the key.

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A friendly note

Information here is general guidance, not a diagnosis. Always speak to a qualified mechanic before parting with cash.

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