How to check a car before buying

You've found the car of your dreams – now you need to check its condition.

We explain how to make sure a car is in full working order when buying.

When you arrive at your viewing, take a look around the car before you ring the doorbell. This gives you a chance to view it without being distracted by the seller. NEVER view a car in the dark or in the rain, as weather can hide a multitude of sins. You'll never spot scratches, dents or rust in the rain, and a lack of light means other potential problems could go unnoticed.

Outside the car

Let the seller show you the car, but don't let them distract you from carrying out your own checks:

1. Walk around the car and check it over. Unless you've been told otherwise, the car should be in a driveable state
2. Crouch down in front of each front wheel and look along the length of the car. Both front wheels should be directly in front of the rear – if they're not, it could mean the car has been in a crash with a slightly twisted chassis or the wheels may require ‘tracking', which is fairly inexpensive
3. The wheels should sit neatly in the wheel arches, equally on both sides
4. Check the gaps between panels are equal. Run your finger along each to feel if the gap is bigger at one end than the other. Uneven panel gaps occur if a car has been in a crash, or if panels have been refitted badly
5. Look carefully at each panel for ripples or overspray – this is where excess paint has flecked onto other trim, such as window seals and bumpers
6. Look closely at each tyre – including the spare. Watch for uneven wear, which could mean suspension damage; nicks and gouges
7. The minimum tread depth is 1.6mm for the whole way around the tyre. Use a tread depth gauge to see how much is left – at least 3mm is recommended
8. Check under the car, particularly at the front and back, under the bonnet and under the boot's carpet for signs of crash damage. Panels should be flat and free from signs of welding or patching up – if they're not, it may have had a shunt
9. Look out for rust – especially around the wheel arches where moisture, grime and winter road salt can increase speed of deterioration
10. Start the car with a cold engine, as this is when it's easiest to spot starting problems or excessive smoke. Place a hand on the bonnet – if it's warm, it's been run recently, so let it cool for a few hours. If need be, come back later

Any shunts could have been caused by minor, low-speed crashes, but you should take extra steps to be sure there aren't any more serious problems.

Ask the seller if the car has been in any accidents. A car history check will let you know if a car is stolen, scrapped, written off or has outstanding finance.

Inside the car

There are plenty of things to check inside – most of which can be a good indication of mileage and how well the car has been looked after.

1. Look around the cabin – a 50,000 mile car shouldn't have a sagging seat or a worn steering wheel, gearknob or pedal covers. If it does, it could be a sign of clocking
2. Make sure all the seatbelts work – they could indicate a previous crash or general neglect. They're a legal requirement too – if the car is being sold with a new MOT certificate, alarm bells should be ringing as these should have been checked
3. Check the dashboard and steering column panels are bolted on correctly – they could point to a clocked car, or one which has been stolen, particularly if there are glass fragments on the floor
4. Don't be too quick to reject a car – it can be tricky to bolt a dash back together after changing a blown bulb in the instrument panel
5. Make sure all switches work – including heaters and air-con – and check the front seats move about properly
6. Locate the Vehicle Identification Number (VIN). You'll find this riveted in the engine bay.
7. Look closely at the dashboard binnacle (which houses the speedometer and other dials). If the car has an older, mechanical-style milometer which turns as you drive, make sure all barrels are aligned correctly – turning these back is illegal.

If there are fingerprints in the dashboard binnacle, ask why – there could be an honest explanation.

This is harder to check on more modern models which have electronic milometers – the miles can be turned back by connecting a laptop and entering a new mileage.

ALWAYS make sure mileage tallies with old MOT certificates and service history.

There are few reasons why the VIN should have been removed, so be suspicious if there are signs of tampering, you could be looking at a clone – a stolen car given the identity of a write-off.

The VIN number will also be stamped in the floor beside the driver or passenger seat, or at the base of the windscreen. A clone will have another number welded on, and are usually quite easy to swap.

Check all numbers match the V5C document (or ‘logbook') and your car history check documents – if they don't, walk away.

Under the bonnet

Any problems you miss under the bonnet could be costly, so check thoroughly.

1. Check for signs of oil leaks around the top of the engine, and underneath too – this is where it'll be most obvious. Road grime can stick to oil, making it more noticeable.
2. Remove the dipstick from the oil tank, wipe it with a cloth and replace for a couple of seconds before pulling it out again. The oil level should rest between the minimum and maximum marks – if not, the owner hasn't been looking after it
3. Oil should be a golden colour – sludgy black oil is a sign of neglect
4. Look around the oil filler cap for a white mayonnaise-like substance - this is an indication of a damaged head gasket, which could point to serious engine damage