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Buying a used car , Safety and breakdowns · Updated 2026-10-15

How to inspect a used car

A careful inspection can save you from an expensive surprise. Take your time, look at the car in daylight, and do not let the seller rush you. This guide covers what you can check yourself; for a final decision, an independent mechanic is worth the cost.

Before you start

Ask the seller to keep the engine cold until you arrive, because some faults only show on a cold start. Bring a torch, a clean cloth, and a friend if possible. Look at the car on level, dry ground.

Walk-around: body, paint and rust

• Stand back and look along each side for waves, dents or uneven reflections.
• Check that the gaps between panels (doors, bonnet, boot) are even on both sides.
• Look for paint that differs slightly in colour or texture between panels, and for paint dust on rubber seals or trim.
• Inspect wheel arches, sills, door bottoms and the boot floor for rust bubbles or flaking paint.
• Check all glass for chips and cracks, and make sure the glass markings look consistent.

Tyres and brakes

Uneven tyre wear can point to alignment or suspension problems. Check that all four tyres are of a sensible matching type and have similar wear. Look through the wheels at the brake discs: deep grooves or a heavy rust lip suggest neglect.

Under the bonnet

• Look for oil or coolant leaks, wet patches and crusty deposits.
• Check the oil on the dipstick: it should not be milky or full of grit.
• Check the coolant level and colour, and the brake fluid level.
• Look at belts and hoses for cracks, and at the battery terminals for corrosion.
• Start the engine cold and listen for rattles, ticking, squealing or rough idling. Watch the exhaust for heavy smoke.

Interior and electronics

• Smell for damp or mould, which can mean leaks or flood damage.
• Check that wear on the seats, pedals and steering wheel fits the stated mileage.
• Test every window, mirror, lock, light, wiper, horn, heater and air conditioning setting.
• When you switch the ignition on, warning lights should come on and then go out. A light that never comes on may have been disabled.

The test drive

Drive on a mix of roads for at least twenty minutes. Check that the car tracks straight, brakes without pulling or vibration, and shifts gears smoothly. Listen for knocks over bumps. Try the car at low and higher speed, and test reverse and the handbrake.

When to involve a mechanic

Ask for a professional inspection whenever you are serious about a car, especially if it is expensive, older, or you are unsure what you are looking at. A seller who refuses an independent inspection is a warning sign in itself. Have the mechanic read the fault memory with a diagnostic tool and check the underside on a lift.

Inspection Safety Used car