10 Simple Steps On How To Clean A Car Engine (E Detailing)

10 Simple Steps On How To Clean A Car Engine

Automobile engines are powerful, important, but are either forgotten or feared.

The engine of our automobiles are constantly overlooked, either because we don't think it's really important, or we are afraid to cause damage to the engine when detailing.

Below we are going to discuss simple steps on how to clean a car engine to make it gleam and shine, which will help maintain your vehicle's quality performance, as well as its resale value.

how to clean your car engine

The Benefits of Cleaning Your Engine

There are two major benefits to engine detailing.


A clean engine is no doubt a happy engine. But cleanliness is for much more than aesthetics. An engine is numerous working parts that depend on each other to run properly.

For example: if you have dirty or corroded battery cables, the battery can't make a proper connection which leaves the car with no power. In newer cars you add in digital components like car alarms and GPS.

These conveniences rely on a digital mother or computer boards that can malfunction with the occasional dust bunny let alone old oil and rust.

Or, how about that lovely smell that comes through the air vents inside your car every time you turn on the heater or air conditioner. These smells are burning dirt that is being sucked in through the intakes and into your face.

Most mechanics agree, a clean engine is important; it means a happy car, a better run car and happier driver. 

Resale Value:

Another benefit to a clean engine is its effect on the resale value. Think about it. Which car would you rather buy the Before or the After?

How To Clean A Car Engine

According to Kelly Blue Book, a vehicle where the interior/exterior cleanliness is well maintained could sell for as much as $1000 more than an unkempt car.

Other sources such as CNN state that the resale value of a car can be improved by 21% just because the car "looks good". Sure a clean engine may not be the first thing that they see, but when they lift the hood, it is definitely the cherry on top.

What Areas Should You Be Careful Around When Engine Cleaning?

Cleaning your engine is not brain surgery, actually it's not even as hard as weeding the backyard. It only takes a little prep work to make cleaning your engine safe and easy for you and the car.

Here are a few tips to keep in mind before we get started engine cleaning:

  • Dont 
  • Just Spray Your Engine with Cleaner. You're going to want a use a degreaser, not an ammonia based cleaner that can cause plastic casings to crack and speed up the erosion of plastic tubing and metal connections.
  • Stand too close when using a hose or pressure. Try standing at least a foot away from the bumper; this will allow for control of your hose or anything with pressure.
  • DO

Protect your wires and other important parts of the car that could be affected by water or degreasers. This step is especially important when using a pressure washer or air dryer to clean your engine. Here is a list of things to cover before you get started.

  • Alternator
  • All Exposed Filters
  • Air Intake
  • Electrical Connections
  • Gauges

Do Not Skip This Step. Taking a few minutes to wrap these components will allow you a stress free engine washing experience. Don't worry about the battery or anything in plastic or metal casings that are already protected. Now that you have all the scary stuff out of the way. Let's get to the cleaning

What To Use To Clean Your Car Engine

  • 2 Types of Degreasing Products (Solvent and Water Based)
  • Air Compressor or A Cloth and Elbow grease to dry the car engine
  • Pessure Washer  or Water Hose
  • Nylon Brush
  • Drip Pans
  • Knee Pads (Optional)
  • Wire Brush
  • Plastic Bag or Aluminum Foil 

Related: Why Does My Car Shake When...?

10 Steps: How to Clean A Car Engine

internal engine cleaning

Step 1: Protect Electrical Wires & Other Important Components

Using a plastic bag or aluminum foil, start by covering all your electrical wires. If the wires or wire casing are dirty, you can clean them by hand once you remove the majority of water from the engine.

Do the same with your alternator, car alarms, and all exposed filters and the air intake.

If necessary use painters tape or twist ties to secure the plastic. Also, check your vehicle's user manual for electronic parts you may not see when you first look into the engine, especially anything digital or connects to the digital parts of your car.

engine cleaning tips

Photo: Wiki How

Step 2: Place The Drip Pan Underneath Your Car

Allowing harmful chemicals to flow into the storm drain is not only bad for the environment it is illegal. To help prevent this place a matt or drip pan under the car to collect and soak up chemicals from the engine and the cleaners.

Keep in mind that the pan will have to be the approximate size of the engine itself. The pan will do no good if the water and chemicals don't fall into it. Please note that collecting the water is only imperative when using solvent based degreasers with oil derivatives. Water and citrus based degreasers are designed to use microscopic amounts of chemicals that are safe.

how to clean internal engine parts

Step 3: Brush Away Loose Dirt & Debris

Before you reach for the cleaner, Use a wire brush and scrub the exposed surface of the engine.

Using the wire brush will start to break away larger debris from the engine, especially when saturating the grime will only cause more mess. You know those globs that just spread once wet. Get rid of these now with a vigorous scrub, but don't be too forceful so that you don't leave scratches.

how to wash a car engine at the carwash

Photo: Cherokeeforum.com

Step 4: Apply Engine Cleaner and Let Soak

Spray the degreaser on all the exposed parts of the engines. Be generous and make sure that you use enough cleaner to remove the dirt.

Pay attention to the part of the engine that you have covered. You don't want the degreaser or water to pool in the plastic that covers it so make sure to avoid these areas. Once you have the engine sprayed, let it soak in for at least 10 minutes. These steps are the most effect portion of how to clean a car engine

Soaking the surface allows the degreaser to work through the grime before you move on to the next step.

Step 5: Agitate The Remaining Dirt

Once the degreaser is thoroughly soaked in, use the nylon brush this time and scrub the surface. Make sure to rub the dirt thoroughly, so that the degreaser lifts the remaining grime from the surface. Removing all the dirt will take a few minutes and a good amount of elbow grease so be patient. I like using the circle technique to keep the grime moving around the surface.

Step 6: Rinse The Engine

Turn on the water hose and clean the degreaser completely off the engine. If you are using a garden hose, place your thumb over half the opening to create a little pressure to help you remove the cleaner and dirt. (Take note that if you are using a pressure washer you'll want to set the pressure low so that you don't damage any parts of the engine.)

Whether you are using a garden hose or pressure washer, be sure to stay aware of the plastic or foil you have used.

Make sure that the water doesn't pull and the pressure doesn't knock the covering off before you can get the engined dried. If you look at the engine, and it's still dirtier than you would like to repeat steps 3 through 6. If you are satisfied with the level of cleanliness, move onto step 7.

Step 7: Dry The Engine

Take a towel and dab up any pools of water that may have formed on your plastic or aluminum foil. Then, turn on your air compressor and using your hose, spray the engine dry.

Once again be careful of the wrapped areas. As an alternative to the air compressor, use a towel to hand dry the surfaces. It will take a little longer, but it will get the job done.

engine detailing

Step 8: Remove Plastic Bags & Dispose of Water

Once the engine is dry and you have checked that there is no water in or on the plastic covering, you can remove the plastic or aluminum from your wires and alternators, etc.

Give the components a once over with your dry rag, or your air compressor on very, very, low pressure. Throw the bags and aluminum away and appropriately dispose of the water in the drip pan or mat.

Again, if the cleaner is water or citrus based you can just throw it in the yard or ditch. If you are using a Solvent based cleaner, you may have to dispose of it with other chemical waste in a proper manner. You can consult your city ordinance for how to do that.

Step 9: Turn Engine On

To remove any excess water, you may have missed, turn the engine on for a few minutes to help evaporate the remaining water. The engine does not have to be completely dry before you start it, but remove all the plastic or aluminum foil first!

Step 10: Step Back & Enjoy Your Work

Finally, take a second to enjoy the beauty that your elbow grease has just produced. So many times we get caught up in doing things to impress others, this time, you can take the moment for you.

how to clean the inside of an engine

Make Cleaning Your Engine Easier

Quick Engine Cleaning Tips

  • Try warming up the car to make cleaning the engine easier. Heating up the engine will help to loosen up some of the stuck on oil and other components that liquefy with heat.
  • Don't leave it on while cleaning, though, and don't warm it up for too long. A hot engine could not only cause injury, but it will also evaporate the cleaner.
  • Depending on the age of your car, most engines warm up within 5 minutes. I wouldn't suggest any longer than that. If you think that you may have left it on too long, place your hand over, not on, the engine. If the engine is hot it was on too long, let it cool down before you start to clean.
  • Use a smaller nylon brush, spray cleaner directly onto brush to get to harder to reach areas.
  • Use solvent based degreaser for incredibly filthy engines.
  • Jack the car up when cleaning the bottom of the engine, but be sure that the car is on a steady flat surface.
  • Since you're already there, think about removing battery cables and give them a scrub. Keeping these cables clean will help extend the life of your car's battery.

How To Clean A Car Engine Without Water

Related: Why Do Cars Depreciate So Quickly?


Now you are a professional (well, kinda). There are so many car owners who don't know how to clean a car engine (or wheels, or tires, etc.) Your car's engine is one of the most expensive parts of your vehicle and as you can see is as easy to clean as the interior of the car.

Engine cleaning will keep you lifting the hood with a smile, help your engine last longer and keep the resale value at it's peak. Make sure to let me know how amazing your engine looks after trying my simple steps. Thanks for reading. Until next time.

Leave a Comment: