How to check and top up your engine oil

Checking and topping up your oil is an essential part of maintaining your car and should be done regularly. Oil is the lifeblood of your engine and works hard to keep it in good working order, so it’s extremely important that the oil itself is in good condition, and that there’s enough of it.

If your oil is left to degrade and deplete, a number of serious issues could occur, many of which could eventually destroy your engine. Fortunately, checking and topping up oil is quick and easy. Here’s how it’s done…

How to check your car’s engine oil (cars with a dipstick)

Firstly, park your car on flat, level ground, and wait for the engine to cool down. This is very important as it will ensure that the oil levels are uniform within the engine, and it also guards against expansion due to heat. If you were to measure the oil while the engine is hot, it might appear that there’s more than is actually present.

Next, open the bonnet and make sure you have some kitchen towel or a cloth to hand. Locate the car’s dipstick - a long, thin metal rod that usually has a yellow or orange plastic handle. This is normally easy to access but will be separate from the oil filler cap.

Gently remove the dipstick, being careful not to flick oil over the engine and other components, wipe it clean, reinsert it, and then pull it out again.

The dipstick has minimum and maximum marks at the end, the design of these marks can vary between cars but should always be clear to read. A healthy engine should leave an oil mark between the two. Preferably, this will be closer to the maximum end than the minimum end, but neither over or under the two markings.

At this point, check the colour of the oil. It should be light and golden in colour. If it’s dark or black, then it’s getting old and you should consider having it changed.

Once you’ve finished checking the oil, you should firmly reinsert the dipstick back into the engine.

How to check your car’s engine oil (cars without a dipstick)

An increasingly common sight on modern cars is the lack of a dipstick. Some manufacturers, such as BMW, have decided to not fit traditional dipsticks to some models, opting instead for a screen readout.

The method for accessing this readout will vary depending on the car, but as a general rule you will need to go through your trip computer’s menu and find the correct option to display your oil level. Check your car’s owner’s manual for details on how to do this.

Unfortunately, without being able to physically inspect your oil, you will not be able to accurately check its overall condition. Therefore, it is even more imperative that you meet the servicing intervals set by your car’s manufacturer in order to maintain the quality.

How to top up your oil

If you need to top up your oil, remember that it’s crucial that you use the correct oil for your engine. Check the car’s handbook to see which oil the manufacturer recommends for the car.

Topping up the oil is very simple. Again ensuring that the engine is cool, unscrew the oil cap, which is usually located at the top of the engine. If you’re unsure about this step, consult your local dealer or check the handbook.

Using a funnel, pour a small amount of oil into the engine, giving it time to settle, then check the oil level with the dipstick. If you still need to add more, simply repeat the process, remembering to add small quantities each time.

Avoid overfilling the engine with oil, as this could lead to significant damage.

If you think you’ve encountered a problem, it’s best to get an expert opinion from a local dealer or garage. Poor maintenance could lead to costly repairs in the future.

Why not give your car a more thorough going over? Read our guides on How to check your car's engine coolant level, how to repair car paint scratches, and how to change a battery.