Is it ok to wash engines anymore?

I remember decades ago that washing car engines was done all the time. You could go to a engine wash shop and get cleaned. Is this even recommend anymore for newer vehicles made in the past 10 years with all the electronics and chips now? Is there anyway to do this and not hurt the newer engines?

Or should I just deal with the dirty engine and let it be.

Steam cleaning places will wrap all the electricals before they wash the engine. Especially if you show the car, you’ll want to do it because they take points off for dirty engines. That said, most modern engines are covered with a decorative plastic cover, so you can just remove that, clean it, and reinstall.

I don’t think washing down the engine bay is a DIY job. There are too many electronics and connectors. If you get too much water in the wrong place the repair can be costly.

I’d trust a “detailer” pro with some experience to do the job. In general, I just keep the engine bay clean with damp rags every now and again.

I avoid it. I just do a hand cleaning with an old t-shirt.

Unless the engine has had some sort of problem that causes an unusual mess, like the iol cap left off, I recommend against home washing of the engine for other than the valid concerns about electronics. Doing so can force water into cavities that were not designed to get wet, cannot dry out well, and cause premature rusting. Professional steam cleaners, like those at detailing operations, are used to doing the job without doing this and steam cleaning machines don’t flood the area with water.

I have a neighbor who washes his engines religiously, and has zero knowledge of auto mechanics. He makes big rivers of water down the side of the road. He can never understand why he’s always having engine problems and his cars never seem to operate dependably. And he gets rot in spots where others do not. He won’t listen to those of us who have tried to gently suggest that perhaps watering his engine compartments isn’t such a good idea.

If the engine is just dirty you should just deal with it and let it be. It’s not hurting anything. If the engine is leaking any fluids, and that is the reason the engine is dirty, you should concentrate on repairing the leak(s), and don’t worry so much about the accumulated greasy gunk on the engine. Leaking fluids are sooner or later going to cause you problems that are much more expensive than what it might have cost to stop the leak.
Otherwise, unless you are showing this car, there is no benefit and a pretty high level of risk involved with cleaning the engine, even if you are just using soap and water.

Sure! You can wash an engine. Todays engine are sealed against moisture better than earlier engines.

There’s fuel injection. No carb to worry about. Direct ignition systems. No distributor to worry about. The electrical connectors on todays engines are sealed against moisture.

I wouldn’t hesitate in washing an engine.


Don’t do it. While technology and quality in vehicles are better nowdays, water has not improved much, especially in vapor form. (:

What I mean is steam can still get in where it does not belong and ruin electronics. I have seen it happen.

If I were you I would simply wipe down the engine with a wet rag.

I wouldn’t. I use rags moistened with an all-purpose cleaner and wipe down everything I can reach. That comes out looking pretty decent, especially if you do it reasonably often.

My owner’s manual specifically states that you should have an authorized service department clean the engine bay (and it doesn’t really recommend that you have it cleaned anyway). This is interesting because all other types of cleaning are spelled out with the type of cleaner to use.

The sensors and low voltage electrical connectors have seals in them and are water resistant enough to keep out the rain water that comes in through the radiator or splashes up from the road, but high pressure sprayers and alkaline cleaners can penetrate electronics and do a lot of expensive damage.

I clean the visible parts with a rag and maybe some WD-40 to soften greasy grunge. When the plastic covers are off, I clean them with soap and hot water. If I have an oil leak, I use engine shampoo and wash only the affected area, which generally has no electronics. I generally wash my cars in the driveway (though I know I shouldn’t, even with biodegradable soap) but cleaning oil leaks off the lower extremities of the engine is strictly done at the car wash. Strong soaps and oil don’t belong in the storm water drain.