GolfGTIforum.co.uk

Model specific boards => Golf mk3 => Topic started by: palmer on 05 February 2011, 00:26

Title: runs bad when I remove the oil cap when running
Post by: palmer 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

Title: Re: runs bad when I remove the oil cap when running
Post by: Jimmy Filth 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:

Title: Re: runs bad when I remove the oil cap when running
Post by: stainesy on 05 February 2011, 07:57

My golf is exactly the same I think its normal on the golf though.

Title: Re: runs bad when I remove the oil cap when running
Post by: Rmachines on 05 February 2011, 08:32

Its normal.  :smiley:

Title: Re: runs bad when I remove the oil cap when running
Post by: Wayne on 05 February 2011, 09:22

Normal  :smiley:

Title: Re: runs bad when I remove the oil cap when running
Post by: 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?

Title: Re: runs bad when I remove the oil cap when running
Post by: boneybradley 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

Title: Re: runs bad when I remove the oil cap when running
Post by: thai-wronghorse on 05 February 2011, 13:27

 :nerd:

Title: Re: runs bad when I remove the oil cap when running
Post by: Mike87Turbo 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!

Title: Re: runs bad when I remove the oil cap when running
Post by: thai-wronghorse 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: