How To Test A Used Car: The Engine

The single most important element in a car has to be the engine. So when you’re looking at a used car to buy, you need to make sure the engine is in full working order before you make a purchase.

Knowing what to look for when testing out a car can be a bit of a mine field. What do you need to look out for? What signs should you be worried about? Well, to help you in searching for your next perfect car we’ve compiled a checklist, so you can give the engine a complete check to make sure everything is running smoothly:

  • Before you start the engine, check underneath the engine oil cap for any thick white substances; these could indicate a problem or that the engine is damaged.
  • Pull out the engine oil dipstick and clean it off with a cloth or tissue, then re-insert it. Pull it out again to check the oil level is at its maximum level and that the oil is clear. If it’s not, then that could be an indication that the car needs a service – which could possibly mean you can bargain on a better price. Oil differs between petrol and diesel engines; diesel engine oil can become quite dark soon after an oil change.
  • Check the body work around the exhaust; a dark oily layer could indicate the piston rings are worn down and need replacing – another thing that could help you talk the price down.
  • Start the engine from cold to assess the engine properly. If the bonnet is warm when you arrive then the engine has already been started, meaning the seller could be trying to hide something.
  • Once you’ve turned the engine on, get out of the car again and watch for any excessive smoke coming from the exhaust. Whilst keeping an eye out, keep a keen ear for any unusual noises the engine might be making.
  • When you first start the engine it’s normal for the exhaust to produce some steam or white exhaust smoke, especially if the weather is cold. If excessive white smoke continues, or the smoke is blue in colour, take these as red flags that something is not right with the engine.
  • When you take the car for a drive, keep checking in your rear-view mirror for any excessive smoke. The engine should tick over quietly when you pull away and gain revs smoothly as you accelerate.
  • After the test drive check for leaks underneath the car – especially around the engine bay.

When buying used cars it is important you make full checks to ensure you don’t get stung by any hidden surprises.