Oil, oil, everywhere

I inavertently left the oil cap off when I added oil about a month ago. After I discovered what I had done, and noted oil everywhere under the hood, I continued to drive the car and nothing seems to be wrong with it.

Is it ok to continue to drive? Are there anythings I should watch out for due to my stupid mistake?

The car has about 120,000 miles on it.


If you haven’t yet, you need to replace the oil cap, and double check the oil level. After that, I would GENTLY give the engine a bath at the car wash. Be careful not to hurt the radiator with the high pressure hose and make sure the engine is warm to help dry the water off. I usually spray the engine while keeping the nozzle at least 2 feet away from the engine. Keep water out of the air intake, use soapy water, and you should be good to go. I’ve washed my engines several times, and rarely have a problem. If it doesn’t start right away, it’ll start after the water dries a bit better.

Actually, the oil cap was right where I left it, on top of the radiator! I did put the cap back on after checking the oil level.

What is the reason to wash the engine, other than getting rid of the burning oil odor?


If this happened a MONTH ago, it’s HISTORY…You should clean up the MESS so dirt and dust won’t continue to stick to it, making an even BIGGER mess to clean up…Look for a product (in a spray can) called “GUNK”…Follow the directions on the can…

Thanks for the suggestions on how to clean up the mess. However, what is the reason to clean it up? Why is it a problem for dust and dirt to stick to the engine? Does it affect its performance or is it asthetic?


A clean engine is a happy engine…
Anyway, it is good to keep gunk off of the ignition system parts at the least. Keeping the engine clean will also make it much easier to work on and make it possible for you to see when it develops a leak somewhere.

I ade a similar mistake once on a road trip in a Mazda Protege. Added oil at a gas stop, and forgot to replace the cap. 300 miles later, stopped at a rest area, noticed an oil burning smell, opened the hood, and saw lots of oil and the cap laying right where I left it on the radiator. I checked the oil, and was down only a half a quart from full. Replaced the cap and continued on.

As long as there was enough oil in the crankcase and the oil light never went on, all you did was waste some oil and make a mess. The engine should be fine.

Ok! Thanks for the comments!

The coating of engine oil will degrade all the wires, hoses and plastic parts over time…Motor oil is a powerful solvent…

Are there any airports near you that cater to general aviation (small) airplanes? If so, you can possibly get an A&P (mechanic) to clean the engine for you. Airplane engines are washed once a year by law whether we owners want it or not. A repair facility has cleaners with solvents that evaporate shortly after spraying. If they’re good enough for a $20,000 aircraft engine, it should be safe enough for what’s under your hood.

I would simply replace the cap and replace your engine oil as it may have gotten a bit dirtier.

Just hope for the best, at least not a brand new car :slight_smile: