Skip to Content

Can You Power Wash a Car Engine?

What was that old wives’ tale about car engines needing dirt and oil to function at their fullest? Something along the lines of ‘the dirtier, the better’?

Well, we are here to tell you that that is untrue. On the contrary, a clean car engine functions better as it can cool itself down more effectively.

Here is how you can and should power wash your car engine.

How Often Do Car Engines Need Cleaning?

We get it. The thought of diving into your car’s engine is enough to make your skin crawl. But depending on the environment in which you live, your car engine may be crying for you to do so.

Over time, engines build up a lot of debris and dirt.

Environments that are prone to a lot of dust, pollution, snow or strong weather patterns will lead to build-up even faster. Cars in these conditions are recommended to be cleaned once every three months.

Environments that are less prone to these harsh conditions don’t require as frequent engine cleaning. Twice a year should be sufficient.

Regardless of the environment’s nature, regular engine wipe-downs should occur between serious washes. This can be done with an everyday hand cloth and toothbrush for the harder-to-reach areas.

This is not as daunting a task as it may seem. Ensure the engine is cold before you start, and you’re good to go.

We love this video where self-proclaimed “car angel” Greg shows you how to give your vehicle an excellent ol’ rub down.

Power Wash or Garden Hose?

Though there is some debate around this question, a power wash is the only practical method of washing a car’s engine.

The truth is a garden hose will only be able to remove the top layer of aesthetic dirt from the hood. The gaps, compartments and harder-to-reach areas will remain filled with debris & build-up. A garden hose creates a blanket of water that covers the entire contents underneath the hood. Over time, the water in the smaller nooks and crannies will result in rust.

Since a power wash operates at such high pressure and allows precision working, certain areas under the hood (that shouldn’t be touched by water) can be avoided entirely. You can target the debris and move on. If a garden hose is all you have to work with, it should be used on low pressure.

Take it slow and strategically avoid areas of the engine that shouldn’t be wet. Ensure the machine is excellent and have a rag handy to scrub along with the hose.

The Benefits of a Good Power Wash

Professional mechanics equate a good engine wash equal in importance to changing a car’s oil or refilling its tires.

If you’re not personally up to regularly power washing your vehicle’s engine, then some places will do it for you.

Most vehicle detailing companies offer this service as an added extra on top of exterior washes. They will power wash under the hood with a high-pressure hose and use degreasing fluids at an additional fee.

You can purchase these fluids if you want to DIY your engine wash.

The most notable benefits of keeping a clean car engine are as follows:

  • The increased resale value of your vehicle
  • The extended working life of the engine and associated parts
  • Improved vehicle safety while on the road

We believe these benefits far outweigh the time and effort it takes to give what’s under the hood a good scrub. Since the car doesn’t care if it’s clean or not, it’s only you who reap the rewards in the long run.

Things to Remember

Do It First Thing in The Morning

The best time to power wash a car engine is in the morning after the car has been sitting cold overnight. Throwing water onto a hot engine can cause extensive damage. What’s more, you risk injuring yourself in the process. A hot motor will burn anything it touches if not handled correctly. Rather avoid this altogether.

Cover certain parts

Before spraying, you must cover the alternator, the engine’s air intake, and other exposed filters. These are just precautions, but getting water or degreaser onto them is not advised.

Use an old grocery packet to cover these parts. Consider doing the same for any exposed wiring that catches your eye.

Apply the Degreaser

Start with the perimeter and work your way in. The best way to apply a degreaser is with a brushing tool.

While a degreaser will not clean the entire engine, it will take care of most of the debris.

Spray Away

Once you’re happy and your degreaser is evenly dispersed — it is time to spray.

With your power wash hose on blast, work your way through the different areas of the engine.

Spray into the hard-to-reach compartments, and when you’re done, give the engine & hood the last spray.

Voila! Like new!


The question is no longer, “can you power wash a car engine?”. Instead, it’s a statement: You should power wash your car’s engine.

The benefit of having a functionally safer vehicle likely to last longer is reason enough to adopt this practice at least twice a year.

We encourage you to take the plunge and do this job yourself instead of seeking a detailer. In the long run, it will save you time and money. All you need is a high-pressure hose and a suitable degreaser. Not that difficult, right?