Mystery fuel line?

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davelarge
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Post Fri Oct 12, 2012 4:54 pm

Hi all, ive noticed there is another fuel line that runs on its own close to the sill, which appears to come from the top of the tank.

The pipe had a 3 inch section of hose half way down the car and from this point the pipe was corroded to where it connected to a rubber hose in the engine bay.

I removed the corroded hose and when i tryed to pull the engine bay end out of where it joined the rubber hose in the bay, the hose followed.. the rubber hose previously went from the fuel pipe and into the chassis of the car underneath the oil resevoir. got a torch into the hole where the hose went and there are no connections.

any ideas?
mcbonio
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Post Fri Oct 12, 2012 5:01 pm

Need to know what year the car is and what engine.
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davelarge
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Post Fri Oct 12, 2012 5:04 pm

1990 318is m42
Topblag
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Post Fri Oct 12, 2012 5:23 pm

is it not the breather pipe from the fuel tank ?
1990 325i Cab auto in Alpine White II
1988 Alpina C2.5 moredoor in Black, 71k
1990 325ix, moredoor auto in Laser Blue. 51k
1984 Hartge H35 in Black
2004 996 C4S in Silver 43k manual
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Brianmoooore
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Post Fri Oct 12, 2012 8:44 pm

If your car had a factory fitted cat. and other emissions equipment, the rubber hose at the front would have connected to a large carbon cannister above the chassis rail, and from there another short hose would have run to a solenoid valve.
If you examine the inlet side of your engine bay, you will find a blanked off rubber hose coming from under the throttle body, which would have connected to the other end of the solenoid valve, and an unused electrical plug on the section of loom leading to the air meter, which is to power the solenoid valve's coil.
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BigDave1
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Post Sat Oct 13, 2012 12:30 am

I found the very same (dead-end pipe and hose combimation) running down from the top breather on the tank to the front of the car where the hose was just poked into a n/s engine chassis section. It ran along the sill area (on OEM clips and studs) and crossed the chassis section under the passenger footwell. My car is a Mar '89 325i M-tech2 - non-cat. I had been wondering why it ran the length of the car and ended no-where in particular. My question is: as it appears this fulepipe and hose combination is not needed at the front, is there a neat and tidy solution that I can use to clip-off the hose at the fuel tank end (next to the fuel filter) rather than just leaving it trimmed off but still dangling?
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davelarge
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Post Sat Oct 13, 2012 3:31 pm

great so its nothing to worry about :) ive already bent the new pipe to replace it so im just gonna fit that to keep it tidy but i guess if you wanted to you could probably fit a stopper to the end of the pipe near where it comes from the tank and secure it out of the way somewhere there?
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Brianmoooore
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Post Sat Oct 13, 2012 11:10 pm

The pipe can be shortened, all the way back to the rear of the car, but most definitely must not be plugged.