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Author Topic: runs bad when I remove the oil cap when running  (Read 1208 times)

Offline palmer

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runs bad when I remove the oil cap when running
« on: 05 February 2011, 00:26 »
is this normal  ?

was changing the oil  and had engine running after it  had been changed  -- removed the oil cap  and to my  " surprise "  the engine then started to run very badly --- replaced the cap  and all was well again !

that is the reason for this and is it  normal ?

cheers

Rob
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Offline Jimmy Filth

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Re: runs bad when I remove the oil cap when running
« Reply #1 on: 05 February 2011, 01:44 »
my knowledge isn't amazing on mechanical things, but I understand that if you do this and there is a change of note it can indicate a problem that I know as 'blow back'.


However I have also been told that this is normal, so I don't know what to believe now  :rolleyes:
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Offline stainesy

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Re: runs bad when I remove the oil cap when running
« Reply #2 on: 05 February 2011, 07:57 »
My golf is exactly the same I think its normal on the golf though.
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Offline Rmachines

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Re: runs bad when I remove the oil cap when running
« Reply #3 on: 05 February 2011, 08:32 »
Its normal.  :smiley:
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Offline Wayne

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Re: runs bad when I remove the oil cap when running
« Reply #4 on: 05 February 2011, 09:22 »
Normal  :smiley:
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Offline thai-wronghorse

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Re: runs bad when I remove the oil cap when running
« Reply #5 on: 05 February 2011, 13:10 »
Isn't it to do with creating an air leak in what is regarded as a closed loop breather system?
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Offline boneybradley

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Re: runs bad when I remove the oil cap when running
« Reply #6 on: 05 February 2011, 13:25 »
Quote from: thai-wronghorse on 05 February 2011, 13:10
Isn't it to do with creating an air leak in what is regarded as a closed loop breather system?

yep
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Offline thai-wronghorse

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Re: runs bad when I remove the oil cap when running
« Reply #7 on: 05 February 2011, 13:27 »
 :nerd:
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Offline Mike87Turbo

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Re: runs bad when I remove the oil cap when running
« Reply #8 on: 05 February 2011, 18:34 »
A lot of cars do it, not just golfs! Theres a vacuum of air within the breather system on an engine, and if you remove the cap it loses vac pressure, same as a split pipe or similar.

My advice, leave the cap on lol!
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Offline thai-wronghorse

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Re: runs bad when I remove the oil cap when running
« Reply #9 on: 05 February 2011, 19:44 »
To be honest i don't understand why you would remove the oil filler cap whilst it's running anyway?  :huh:
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