Carautonomy — car parts and warning lights explained
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Engine

What is an Air Filter?

Keeps dirt and grit out of your engine.

ENGINE AIR FILTER — CUTAWAYUNFILTERED AIR INFILTERED AIR → INTAKEIntake restrictionPleats multiply surface area —more dust held, less airflow lostClogged filter = poor MPG & power

Simplified animation — not to scale.

In plain English

A pleated paper or cotton filter sitting in the airbox between the outside world and the engine intake. Every breath the engine takes passes through it.

A simple analogy

"It is the engine's face mask — cheap, easy to swap, and the engine breathes a lot easier with a clean one."

How it works

As air is sucked into the engine, the filter traps dust, pollen, leaves and insects so only clean air reaches the cylinders. Over time it clogs and starts to choke the engine.

Signs of trouble

  • ⚠Reduced acceleration or sluggish response
  • ⚠Slight drop in fuel economy
  • ⚠Black smoke from the exhaust
  • ⚠Whistling or sucking noise from the intake
Rough UK cost

£25–£75, often done as part of a service

Parts: £10–£35
Labour: £15–£40

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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