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Exhaust

What is an Exhaust System?

Carries waste gases away and quietens the engine.

EngineCatSilencerEngine → cat → silencer → tailpipe

Simplified animation — not to scale.

In plain English

The full run of pipes from the engine to the back of the car: manifold, catalytic converter, particulate filter (diesels), silencer(s) and tailpipe.

A simple analogy

"It is the car's breathing-out plumbing — pipes, filters and mufflers that send the smoke out the back politely and quietly."

How it works

Hot, toxic exhaust gases leave the cylinders, get cleaned by the catalytic converter and DPF, then pass through silencers that absorb the noise before exiting the tailpipe.

Signs of trouble

  • ⚠Loud, deep rumbling or rasping noise
  • ⚠Rattling from under the car
  • ⚠Smell of exhaust fumes inside the cabin
  • ⚠Failed MOT on emissions or noise
Rough UK cost

£150–£900 depending on section

Parts: £80–£600 per section
Labour: £80–£250

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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