car stalls when i remove oil cap..

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kangman
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Post Tue Sep 18, 2012 9:43 am

when i remove the oil cap of the 318is engine it stalls, when it warmed up i removed it again and it stalled. Restarted it and it never staled but it was spitting oil out..

Is that normal?? my other two e30s never did that, the revs just dropped
johnl320
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Post Tue Sep 18, 2012 8:29 pm

You are introducing an air leak into the inlet manifold via the engine breather pipe
cecotto479
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Post Tue Sep 18, 2012 8:32 pm

It shouldn't stall as in stop running, but it should start to idle a bit "rough". It'll do this if you take the dipstick out or unplug the hose from the rocker cover. Effectively you're opening the sealed crankcase breathing system to the atmosphere.
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mark_i
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Post Wed Sep 19, 2012 1:54 am

thats normal for the engine (m20, m40, m42) to stall or at least run lumpy... the rocker cover is connected to the inlet by the breather hose, so removing the oil cap introduced a large air leak...
oil will splash out of the filler if the engine is running, although with an m40 there is a baffle plate which minimises that.
magpie
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Post Wed Sep 19, 2012 8:34 am

to QUOTE DanThe .........

"remember Kids the engine runs better with the oil cap on"


:mrgreen:
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m52 b30 stroker 6-speed 318is Galvanizer
m42 touring
+ a yard full of scrap turds :)
FinalD
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Post Wed Sep 19, 2012 9:05 am

willnz wrote:cleaned up. Stick to answering the question, not increasing your post count...
lol?

I don't give a flying one about my post count, my post was just having some fun. Jeez lighten up. :roll:
cecotto479
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Post Wed Sep 19, 2012 10:00 am

willnz wrote:cleaned up. Stick to answering the question, not increasing your post count...

Pot.

Kettle.

Again.

Arsehole.
1981 E23 735i
1989 E30 325i Motorsport Convertible
Bavarian Retro - Classic BMW Cars, Parts and Accessories - 12.5% discount for forum members on E30 parts - use voucher code "E30zone" at checkout