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Q: some smoke and oil droplets

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when I open the hood of the car, there is a cap that when i twist to open (filler cap), there is a tiny bit of SMOKE and few OIL DROPLETS coming out. Does that mean there is something wrong with the engine or it is a normal thing to have. and why? Thank you for your time.

My car has 120000 miles.
My car has an automatic transmission.

A: Presumably, when the engine is hot, you are...

Presumably, when the engine is hot, you are opening the large oil filler cap located on the valve cover. If the car is running when you open that cap, the oil supplied under pressure to the valve train could spatter out a bit, and yes you would see, not smoke (nothing is burning) but rather oil vapors, steam, or condensed "matter" because the hot vapors are hitting colder air and condensing. This is normal.

Generally, there is a baffle in the filler hole to prevent any significant amount of oil droplets from spraying out. At any rate, you should NOT open the oil filler cap, or really any openings to the engine or general accessories when the engine is running unless you have specific technical advice. If you get spattered in the eye with a hot oil droplet, that’s a problem and if you open the radiator cap when the engine is hot you will get burned. The most important thing when it comes to engine oil is to maintain it regularly.

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