Skip the auto shop - Our mechanics make house calls

Q: some smoke and oil droplets

asked by on

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.

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. some smoke and oil droplets

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: oil inside spark plug chamber and clicking/ticking

Hello - oil is leaking from the valve cover, down into the spark plug recesses as you noticed. This causes the spark plugs to short, creating the misfire you have experienced. No doubt some of this oil leaked into the...

Q: How do I use the interior door lock switch?

The interior door lock switch is located on the driver’s door panel. The switch has both a lock button, and an unlock button. Press the lock button once to lock all of the doors, or press the unlock button once...

Q: smoking!!!!!!!!

If you are getting excessive smoking from the oil that was spilled then you should have the engine cleaned off. The excessive oil should be removed to prevent the possibility of a fire caused by the oil. If you'd like...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...