How to Clean Car Engine

What You'll Need

• Engine degreaser
• Plastic bags and tape
• Stiff brush
• Garden hose
• Microfiber cloths
• Compressed air (optional)

Step-by-Step Instructions

1. 1

   Cool the engine completely

   Never spray water on a hot engine. Let the car sit for at least 30 minutes after running so the engine is cool to the touch.

2. 2

   Cover sensitive electronics

   Cover the alternator, battery, distributor cap, air intake, and any exposed electrical components with plastic bags secured with tape.

3. 3

   Apply engine degreaser

   Spray engine degreaser generously on all greasy surfaces. Let it sit for 5-10 minutes to break down oil and grime.

4. 4

   Scrub stubborn grime

   Use a stiff brush to scrub heavily soiled areas like the valve cover, intake manifold, and oil pan exterior.

5. 5

   Rinse with low-pressure water

   Rinse off the degreaser with a garden hose using gentle pressure -- never use a pressure washer. Avoid spraying covered electronics.

6. 6

   Dry and remove covers

   Wipe down the engine with microfiber cloths. Remove plastic covers carefully. Start the engine and let it run 10 minutes to evaporate remaining moisture.

Pro Tips

• TIPTake photos before cleaning so you can identify any leaks or issues that become visible after the grime is gone.
• TIPUse a foaming engine degreaser that clings to vertical surfaces longer than liquid sprays.
• TIPClean your engine bay every 6-12 months -- it makes spotting leaks and maintenance issues much easier.

Common Mistakes to Avoid

• XUsing a pressure washer, which forces water into electrical connections and damages sensors permanently.
• XCleaning a hot engine, which causes thermal shock that can crack components.
• XSkipping the cover step, which lets water into electrical components and causes intermittent issues.

Frequently Asked Questions