How To Clean Your Engine

Don't forget your car's engine compartment.

As a young man growing up in the 60's and 70's, I always cleaned my car's engine when I washed the car. There was no particular reason I did this, I just felt better driving a car with a clean engine! Things are different now. I can give you some real good reasons for cleaning your car's engine besides vanity. First, engine compartments are getting smaller and more cramped. This concentrates heat and grime closer to hoses, wires, plastic parts and vinyl trim covers, all of which can degrade and crack over time. Oh yes, remember that radiator hose that cost you $2.95 in the 60's? Todays molded hoses can now cost $100 to $150 or more! That's a pretty good reason to keep them clean and protected. You could also make the case that a clean engine compartment will increase the resale value of your car when you go to sell it.

Following is my system for cleaning engines. I've used this system for decades and never, ever had a problem but our company's legal advisor insists that I add this disclaimer: "Always check with your dealer before cleaning the engine for the first time to determine if there are any special precautions to be taken with your particular make and model of vehicle."

Proper Engine Cleaning

Upon opening the hood, I want to remove any loose grime, pine needles, leaves and dead squirrels that are trapped in the grill or vents. I happen to have a motorcycle dryer (The Black Baron Dryer) that I use to blast off loose debris but compressed air, a leaf blower, or an old paint brush will work just fine.


Use a motorcycle dryer or compressed air to remove loose engine debris.	If you do not have a dryer or compressed air, an old paint brush will work just fine.

Next, I start the car and let it run for a few minutes. The engine should be warm but not so hot that you can not lay your hand on it.

Now turn the engine off and block the air intake to prevent water from entering the engine. If the air filter has an opening, I will plug it with a rag or fit a plastic bag over the opening with a rubber band. You may have to follow the air duct to the front grill to find the opening.

ProperAutoCare.com offers Premium Car wax, Car Polish, Car Care Products, Car Detailing Supplies and Car Accessories.

Plug air intake with a rag.

If you own a collector car with a distributor, you may want to cover it with a plastic bag or aluminum foil to keep it dry.

Newer vehicles have sealed coil paks and ignition modules. Over time, seals can become brittle and crack. If your vehicle is five or more years old, consider covering coil paks and ignition modules with aluminum foil before cleaning.

Now I'll spray the warm engine liberally with a citrus-based cleaner. I like P21S Total Auto Wash. I do not like and do not recommend acid-based engine cleaners. Avoid getting engine cleaners on exterior paintwork. Total Auto Wash will remove existing wax.

I'll let Total Auto Wash soak on the engine for about 3 minutes. During this time, I'll use the E-Z Detail Brush to get into all the nooks and crannies. Next, I'll rinse the engine thoroughly with a garden hose set for medium pressure.

ProperAutoCare.com offers Premium Car wax, Car Polish, Car Care Products, Car Detailing Supplies and Car Accessories.

Spray engine & compartment with
P21S Total Auto Wash.


While cleaner is soaking, use the E-Z Detail Brush to get into all the nooks and crannies.	Rinse with a garden hose and inspect for any missed grease or grime spots.

I'll now go back and inspect for any remaining grease or grime spots that might require special attention. If I find any, I will spray the spot again with Total Auto Wash, agitate the spot with a One Inch Detailing Brush and rinse.

After the final rinse, I'll blow the engine dry with my motorcycle dryer. If you do not have a dryer or compressed air, remove the rag or plastic bag covering the air intake and start the vehicle. Let it idle for 5 minutes.

ProperAutoCare.com offers Premium Car wax, Car Polish, Car Care Products, Car Detailing Supplies and Car Accessories.

Spot clean remaining spots with a
One Inch Detail Brush.

Note: Some performance engines have deeply recessed spark plug openings that can fill with water. Remember to wick-out water with a sponge or blast out water with a dryer before starting the car.

Protect and Beautify

After everything is dry and the engine is cool, apply a protective dressing to rubber hoses, wires, vinyl and plastic shields. I use 303 Aerospace Protectant. I'll spray the top and sides of hoses and then use a cloth to treat the underside of the hose. If your engine has a plastic cover or heat shield spray and wipe that with 303 also.

Wipe off excess protectant with a dry cloth.

ProperAutoCare.com offers Premium Car wax, Car Polish, Car Care Products, Car Detailing Supplies and Car Accessories.

Spray hoses, wiring, plastic & vinyl
with 303 Aerospace Protectant.

There are spray-and-walk-away engine dressings but I'm not a big fan of these products unless you're driving directly to your dealer to sell your car. These dressing stay wet for days and attract dust and dirt. I find that after 5 days your engine is dirtier than if you had done nothing.

Finishing Touches

This Mini Cooper has silver painted metal framing on either side of the engine. I mist and wipe this paintwork with BLACKFIRE Ivory Carnauba Spray Cleaner/Wax. I also use this to spray and wipe any black metal engine cross members and on painted metal air cleaners. This is a little extra effort but it only takes a minute and it makes the entire engine sparkle.

On the picture below, the black panels on either side of the engine that form the wheel arches are plastic not metal. The black heat shield on top of the engine is also plastic, not metal. You can use 303 Aerospace Protectant on these surfaces for a satin finish but I prefer to mist and wipe these panels with BLACKFIRE One Step, Plastic Cleaner, Polish & Glaze. The Blackfire Plastic Cleaner wipes off very easily and leaves more of a shine.


I use BLACKFIRE Ivory Carnauba Spray Cleaner/Wax on Silver body framework.	Black wheel arch panels here are plastic. I treat these with BLACKFIRE One Step Plastic Cleaner, Polish & Glaze.

ProperAutoCare.com offers Premium Car wax, Car Polish, Car Care Products, Car Detailing Supplies and Car Accessories.

Before cleaning.

ProperAutoCare.com offers Premium Car wax, Car Polish, Car Care Products, Car Detailing Supplies and Car Accessories.

After cleaning.