Fuel tank pressure

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EOS
E30 Zone Newbie
E30 Zone Newbie
Posts: 215
Joined: Wed Oct 19, 2005 11:00 pm
Location: Eastwood - Essex

Post Tue Aug 01, 2006 7:30 am

Everytime i take my fuel cap off after a short / long drive there seems to be alot of pressure built up in the tank and hisses loudly when the cap is taken off.

Im thinking its got something to do with this (pic below No1). It has a connector on it and guessing its meant to open up when the car is started then close when the cars turned off, to stop the pressure building up in the tank? Im not sure tho, can someone verify this before i start playing with it. Thanks.

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Morat
E30 Zone Team Member
E30 Zone Team Member
Posts: 8943
Joined: Thu Feb 09, 2006 11:00 pm
Location: The Peoples Republic of Yorkshire

Post Tue Aug 01, 2006 2:08 pm

Are you sure it isn't air rushing _into_ the tank? Normally air has to go in to replace the volume of fuel used by the engine. Sometimes this stops happening due to a blockage and you can end up with the fuel cap stuck on the filler pipe!
E30 Touring 0.35 cD - more slippery than prison soap :)

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Praise the Lard... and pass the dripping!
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EOS
E30 Zone Newbie
E30 Zone Newbie
Posts: 215
Joined: Wed Oct 19, 2005 11:00 pm
Location: Eastwood - Essex

Post Tue Aug 01, 2006 2:12 pm

Yeah it is air rushing into the tank, thats why i thought it was item No1 not been activated to open up the breather pipe. Should this pipe be open when the cars on to let the petrol tank breath and then closed when the cars off? Sorry if the oringinal post wasn't that clear was early in the morning :mad:
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