How to Clean an Engine Bay

Find out how to clean an engine bay the right way and learn what not to do as our mechanic Andy gives some tips in this article and video to help you get your engine bay clean like a pro.

The Right and Wrong Way to Clean an Engine Bay

How to clean an engine bay

  1. Don’t Spray Pressurized Water into the Engine Bay

    Outside the car, you can spray anywhere, but it’s not a good idea to just spray randomly into the engine bay to clean it, and it’s also not a good idea to use a pressure washer.

    The engine bay is made to handle water, and it’s okay to get the engine bay wet, but it’s not made for extreme pressure.

  2. Don’t Spray the Engine While It Is Running

    Spraying a hot engine with cold water can cause issues and may crack components. You could also hydro-lock the engine if a vacuum hose is disconnected.

    Flammable cleaner can also cause a fire if the engine is hot and it mixes with oil.

  3. Don’t Spray the Serpentine Belt, Alternator, Ignition Coil, and Other Electrical Parts

    Keep water away from the serpentine belt, the alternator, the ignition coils, which can arc out and malfunction, the fuse box, and the computer.

    Electrical connectors are weather-proof, but not pressure-water proof. Corrosion can form if moisture gets in, which can cause future problems like your car not starting.

  4. Don’t Spray Debris out of the Cowl Panel

    Using water to remove dirt and debris like leaves off the cowl panel can clog the drain or send water to the floor inside the vehicle.

  5. Don’t Use Flammable Cleaner

    Using flammable cleaner, especially on a hot engine that has oil, can cause a fire.

  6. Don’t Spray the Battery

    The battery has vents, and you don’t want water to leak inside, but you can clean the top.

  7. Make Sure the Oil and Transmission Dipsticks Are Sealed and Secure

    Before cleaning, make sure the oil and transmission dipsticks are tight and secure and not loose to keep water from leaking inside.

  8. Remove Debris from the Cowl Panel by Hand and then Vacuum It

    Remove any debris like leaves with your hands from the cowl panel. Vacuum remaining debris from the cowl panel.

  9. Remove Dirt and Debris from the Engine Bay with a Blow Gun

    Use a blow gun, reverse function on a vacuum, or even a leaf blower to remove dirt and debris from areas inside the engine bay.

  10. Clean Dirty Areas with an Engine Degreaser and Water Mixture and Avoid Electrical Parts

    Mix engine degreaser and water into a spray bottle and spray dirty areas you want clean. Clean the top of the fuse box and the air filter box, the air intake tube, and the top of the battery. Clean the sides of the engine and the top of the engine cover.

    Avoid areas with electrical parts like the alternator, ignition coils, the computer, and the electrical connectors.

  11. Remove Grease with a Rag and Brush

    After spraying areas with the engine degreaser and water mixture, remove any grease with a rag and a brush.

  12. Lightly Rinse the Engine and Dry the Engine Bay

    You can lightly rinse the engine off, and you can remove and wash any plastic covers. Dry the engine bay by blowing air or letting it sit with the hood open.

  13. Spray Rubber and Plastic Protectant

    You can use a plastic or rubber protector, but use one that will work under the engine.

Expert Tips to Diagnose and Fix Your Own Car

Use tips and step-by-step instructions from our mechanics to diagnose and fix parts on your car with 1A Auto’s how-to videos. Our how-to video library has tips, tricks, and instructions for repairing and diagnosing parts on many makes and models.

Related Content

Shop Parts and Tools

Fix and clean an engine bay yourself with quality auto parts and tips at
How to Clean an Engine Bay - Expert Advice - 1A Auto
Article Name
How to Clean an Engine Bay - Expert Advice - 1A Auto
Find out how to clean an engine bay the right way with this article and video as our expert mechanic reveals the dos and don'ts of cleaning an engine bay
Publisher Name
1A Auto
Publisher Logo

Leave a Reply

Your email address will not be published. Required fields are marked *