My son forgot to put the oil cap on my 93 Toyota Celica, and I drove it to work and back (approx 20 miles) before it belched up all the oil. New oil put in, car is holding oil for past 2 days without being driven. Will it be okay to drive and check oil frequently?

No, you want to get a cap on it asap. Driving without a cap allows contaminates to enter
Into the oil and also affects the air pressure of the pcv system. Caps are not that expensive at the auto parts store.

If I had a dime for every time I've seen this, I'd match Donald Trumps' wallet.
Put a new cap on it, and go buy some engine cleaner. Made a mess, didn't it? Then drive it.
Tell son to always cross your T's, and dot your I's before closing the hood.

That's right, it's OK to drive, but not the best for the engine. That's what Vandy-1 was saying. What happends is without the cap on, this disrups the crankcase ventilation system. A PCV valve on the valve cover controls that.
Within the engine is pulses of air called blow-by. It's from the pistons moving. Add that to the hot oil and gasses are formed that are supposed to be recycled to the combustion chambers.
Positive ventilation is what you had coming out the cap hole. Not good, but I've seen customers drive until their next oil change until the missing cap is discovered.

Is there anyone old enough out there to remember the old Ford Falcons as they sat there idling with steam coming out from the bottom? That's because they didn't have a PCV (positive crankcase ventilation) system.
Best wishes.

Buy oil cap for a few dollars and drive it. No nocking in engine,it's probably just fine.

"widowcar disagrees: Not as dumb as I seem, I put the cap on, my questions was about residual to engine."



Lame of you to disagree when I gave you reasons to not drive without a cap
For better help in the future clearly state what you want to know.
FYI: People who answer questions here do it without compensation.

Thanks!

Quote:

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Originally Posted by kitch428

That's right, it's ok to drive, but not the best for the engine. That's what Vandy-1 was saying. What happends is without the cap on, this disrups the crankcase ventilation system. A PCV valve on the valve cover controls that.
Within the engine is pulses of air called blow-by. It's from the pistons moving. Add that to the hot oil and gasses are formed that are supposed to be recycled to the combustion chambers.
Positive ventilation is what you had coming out the cap hole. Not good, but I've seen customers drive untill their next oil change untill the missing cap is discovered.

Is there anyone old enough out there to remember the old Ford Falcons as they sat there idling with steam coming out from the bottom? That's because they didn't have a PCV (positive crankcase ventilation) system.
Best wishes.

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Good insight Kitch 428 your knowledge is helpful to all who will listen !

Good discussion... funny, I just changed the oil in my Toyota van and noticed the oil cap was not on... I found it wedged between two engine components. So I figure I forgot to put it back 6000 miles ago. I changed the oil and the van drive fine. And, I'm refurbishing a 1965 Ford Falcon! As Kitch428 mentioned, the oil cap on the Falcon is not a leak tight seal, so fumes spew out the top of the engine block. And indeed, the oil that comes out of the Falcon is filthy, yet the beast is practically bomb-proof.

I forgot to put the oil cap on my dad;s 1993 dodge caravan v6 allwheel drive, after a refill of 10 w 30, and drove it for about 3 weeks? The hood release was broke so I didn't know until he fixed the hood.