How to Clean and Degrease Your Car’s Engine

How To Clean And Degrease An Engine - Featured ImageHave you noticed that your car’s engine is running much hotter than usual lately? What about experiencing all-too-frequent engine part failures? Your engine may be suffering from chronic grease buildup.

If you haven’t had your car engine degreased frequently, you’re doing your engine a disservice.

The consequences of heavily greased engines include:

  • Higher engine temperatures
  • Increased wear and tear on core components
  • Foul smell

Degreasing doesn’t have to be a big production which costs you hundreds of dollars. You don’t need to be a professional to degrease your car’s engine – you can do it cheaply and easily at home in your garage.

In this article, we’ll explain how you can degrease your engine safely and effectively while on a tight budget.

Preparing To Degrease Your Engine

You’ll need the following materials to successfully degrease your car engine:

  • Drop towel to catch dripping
  • Gloves
  • Goggles
  • Clothes you don’t mind getting stained
  • A hose or bucket with water
  • Degreaser solution
  • Steel brush
  • Weakly adhesive tape
  • Aluminum foil

The exact degreaser solution you choose for the job can vary. Solvent-based degreasers are better for the metal parts of your car and do a complete cleaning job. Nonetheless, they easily corrode non-metal components like rubbers, and they’re especially bad for any electronics that they come into contact with.

Furthermore, solvent degreasers often smell very bad, and they might even be hazardous to the touch. In contrast, water-based degreasers are slightly less effective, but they’re much safer for the non-metal parts of your car. They’re also much safer for your skin and the environment.

No matter the degreaser you pick, you should be sure to wear gloves and goggles. The degreasers aren’t good for your skin, and they can be horrible for your eyes in the event of accidental exposure.

Knowing whether you did an effective degreasing job requires planning. Turn on your car and let it run for ten minutes. Check your engine temperature and write it down. Later, we’ll see how effective our degreasing job was by seeing if the engine temperature is lower than before.

Once you have all the materials and temperature measurement, turn off your car and put a towel underneath the car so that any dripping won’t damage your garage floor or contaminate your yard.

Make sure that the engine has cooled down to ambient temperature before starting the degreasing process.

Next, pop the hood open and cover electronics and non-metal parts with the aluminum foil.

If you don’t want to use the aluminum foil, you can also use plastic wrap.

Rinsing And Initial Degreasing

The first order of business is to remove any clumps of dirt or dust which may have accumulated on the engine itself. You can blast them with the hose, wipe them off with a towel, or brush them away with your brush.

If you get the parts of the engine wet that you plan on degreasing, you should wipe the water off if you plan on using a solvent based degreaser. If you’re using a water-based degreaser, you don’t need to worry about any trace liquids.

Once the area is clean, it’s time for the first round of degreasing. Spray on a liberal amount of degreaser onto the engine surfaces that you need to be cleaned. Make sure to avoid spraying any of the degreasers on to the non-metal parts of the engine!

If you accidentally spray degreaser onto these parts, you should immediately wash it off with water. Leaving it on will degrade the material.


After the first round of degreaser, you should let the degreaser soak into the engine. Read the instructions on your degreasing product and follow them closely.

Typically, you can expect to soak the degreaser into the engine for at least three minutes. The heaviest of grease buildup may take as long as ten minutes before it is ready to be dislodged.

Rinsing And Cleanup

As the degreaser loosens the grease and any caked materials, you can start to remove the largest areas with a brush after the soaking period. Scrub gently with the brush, unseating as much of the buildup as you can.

If there are still obvious areas of grease or grime which seem intractable after the first soaking you should apply another coat of the degreaser and try again after another soak. Avoid applying too much pressure with your brush to avoid scarring any of the metal.

When your engine looks suitably degreased, it’s time to rinse the chemicals away. The trick is to avoid any high-pressure application of water. You want a slow trickle from the hose, held close to the engine areas which were cleaned. Cold water is suitable.

You should see the degreaser and any remaining grime flow off of the engine effortlessly with the help of the degreaser.

This is where you will notice the difference between the solvent based degreasers and the water-based degreasers. The solvent based degreasers will encapsulate the grime more readily and help it to be whisked away by the water with less effort.

You should expect to rinse for a bit longer when using a water-based degreaser.

Dry The Area

After rinsing, vigorously dry the engine with a towel or rag. It doesn’t need to be dry, just dry enough that there won’t be any appreciable steam building once you start the car and the engine heats up.

To dry wet crannies, a hair drier may be useful. You could also wait a long period for the engine to dry out before starting the car, but this typically isn’t necessary. A little bit of steam is okay – just don’t be alarmed when you see it coming out of your hood after you start the car.

Start The Car

Now that your car is fully degreased and dried, it’s time to start the car. Keep your eye on the engine temperature to see how effective your degreasing routine was.

Degreasing your engine will not:

  • Fix issues with your engine’s electronics
  • Improve your gas mileage
  • Prevent subsequent grease buildup
  • Weatherize your engine

If your car is still having issues, you may need to do something more intensive than quick degreasing.

Brett Gordon

The engine behind editing at DigMyRide and the brains behind its build. During the day, Brett is a thirty-something dude from SoCal climbing the corporate ladder, but by night, he spends his time contributing to the online world of automotive tech & trends.