Engine stalls if oil fill cap is removed while idling
Then don’t do that anymore .
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Why are you opening it while it’s running? See that’s how “Ask Someone Who Owns One” works. You actually ask a question.
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That would keep oil from getting thrown all over the inside of the hood and the top of the engine. (I know from experience - my 1984 Chevy Cavalier lacked that feature, at idle and at normal running RPMs!)
Even though it usefully prevents oil from being blown around the engine compartment, do you think it’s a deliberate design feature? If yes, how is it implemented?
Or is it fortuitous, and what makes it happen?
Or is it revealing some problem?
It’s normal.
When you remove the oil cap it creates a massive vacuum leak.
This then causes the engine to run so lean that it stalls out.
Tester
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I just have to ask . Why are you taking the oil cap off while the engine is running ?
I had a car that ran OK with the oil cap off (1984 Cavalier) and haven’t tried it on others. Fortunately I caught it within a block or two, due to a different sound from under the hood, and stopping to investigate. I was about to drive 335 miles and it could have become a really bad thing.
I, too, wonder why some do and some don’t run with the cap off.
Tester — Thanks for the explanation.
V70 — I didn’t remove the cap. The Trusted Independent Mechanic left it loose after an oil change (and some other maintenance).
2004 Camry 4-cyl ran fine, except for the smell of hot oil and the oil sprayed around the engine compartment. L
Is art1966 and E.Goar the same person ?
The pathway for such a leak presumably is the pcv system. If OP has an experimental mind-set, could try temporarily blocking the part of the PCV system that feeds the air intake, the hose to the throttle body or the like) at same time as removing oil cap. If vacuum leak is the reason, engine shouldn’t stall.
No. No other identies.
I had that happen about 40 years ago at a dreaded quick lube place. I got a couple miles down the road and the smell of oil in the engine was strong. I opened the hood, noticed the missing oil cap, and promptly drove back to the lube joint. They filled me up, steam cleaned the engine bay, and apologized profusely. The car ran fine after that.