What is this hose/vacuum line?

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chilone
Posts: 47
Joined: Jun 27, 2022 9:59 AM
Location: Colorado

What is this hose/vacuum line?

Post by chilone »

I posted this question in my 'Eye Candy' post, but I realize that being a tech question, it might not be read my someone who knows.

Anyway, the hose in question goes down past the injector. It connects to nothing and doesn't look like it ever connected to anything. I haven't been able to find any info on what it is, does, or goes. Does anyone know?

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BDKawey
Posts: 1325
Joined: Sep 15, 2011 11:05 PM
Location: Carrollton, Ohio

Re: What is this hose/vacuum line?

Post by BDKawey »

http://forums.bimmerforums.com/forum/sh ... acuum-line

Does this help diagram help? its a m30b35 however, could be the same. you'd be looking at the valve cover T.

looks like it is depicting the lower right nipple on the which can be seen in this thread. see if thats open for use.

viewtopic.php?t=148233
chilone
Posts: 47
Joined: Jun 27, 2022 9:59 AM
Location: Colorado

Re: What is this hose/vacuum line?

Post by chilone »

BDKawey wrote: Jun 29, 2022 4:23 PM http://forums.bimmerforums.com/forum/sh ... acuum-line

Does this help diagram help? its a m30b35 however, could be the same. you'd be looking at the valve cover T.

looks like it is depicting the lower right nipple on the which can be seen in this thread. see if thats open for use.

viewtopic.php?t=148233
That looks like it could very well be it. I'll have to check when I get home. It definitely seems to have a vacuum leak. Thank you!!
Mike W.
Posts: 26872
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: What is this hose/vacuum line?

Post by Mike W. »

I think it goes to one of the vacuum fittings on the bottom of the intake manifold. Seems like there's one for the FPR, one for the interior temp sensor, and one for the crankcase. Since BMW didn't use a PCV they still had to use something at idle, and at idle the throttle butterfly which is where the big hose goes to, is nearly closed. At larger throttle openings that little hose might not be enough so they use the big one.
chilone
Posts: 47
Joined: Jun 27, 2022 9:59 AM
Location: Colorado

Re: What is this hose/vacuum line?

Post by chilone »

Mike W. wrote: Jun 29, 2022 4:48 PM I think it goes to one of the vacuum fittings on the bottom of the intake manifold. Seems like there's one for the FPR, one for the interior temp sensor, and one for the crankcase. Since BMW didn't use a PCV they still had to use something at idle, and at idle the throttle butterfly which is where the big hose goes to, is nearly closed. At larger throttle openings that little hose might not be enough so they use the big one.
That makes perfect sense. Thank you!
LarryM
Posts: 1222
Joined: Feb 01, 2008 11:40 AM
Location: SoCal

Re: What is this hose/vacuum line?

Post by LarryM »

This topic was recently discussed:

viewtopic.php?t=158420
chilone
Posts: 47
Joined: Jun 27, 2022 9:59 AM
Location: Colorado

Re: What is this hose/vacuum line?

Post by chilone »

LarryM wrote: Jun 30, 2022 12:03 AM This topic was recently discussed:

viewtopic.php?t=158420
Thank you! :)
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