Hi folks, quick question for you; what are the two pipes that weave themselves through the intake manifold, one is connected to the underside of the throttle body intake and the other is connected to the rubber air intake boot via a small 90 degree elbow? I have an E30 3.18i with the M40 engine. They mate together half way down their length (although I don't think they are open to each other) and have numerous jubilee clips down their length, they are around a foot in length and just under an inch in diameter. Mine is split at the intake boot and I wonder what effect this would be having on my air/fuel mix.
Any help would be very much appreciated.
Murdo
What is this piping for?
Moderator: martauto
it probably isnt water since he is saying its coming from the intake boot.
the one coming from the rubber intake boot is usually vacuum for the idle control valve
if its split and leaking you would probably notice that engine is not running well
the one coming from the rubber intake boot is usually vacuum for the idle control valve
if its split and leaking you would probably notice that engine is not running well
- mwggriffiths
- E30 Zone Newbie

- Posts: 156
- Joined: Mon Nov 14, 2011 11:00 pm
- Location: Solihull
The one attached to the intake boot is for the idle control valve. The ICV itself is located at the back of the engine, by the bulkhead on the intake/passenger side.
The split hose there may cause idle issues, stalling and so on
If those are the issues you're having then that's your cause 
The split hose there may cause idle issues, stalling and so on
1990 318iS, 1998 E36 328i Touring, 2001 740i Sport, 1971 Range Rover
- otterstricks
- E30 Zone Newbie

- Posts: 22
- Joined: Thu Jun 21, 2007 11:00 pm
Thanks for the replies fellas, I've been away all week so have just checked the post. Cheers for your input, it looks like it is the for the idle control as is does lead to a unit at the back of the engine. I've ordered new and hopefully this will help her run more smoothly.
Cheers folks
Murdo
Cheers folks
Murdo

