over the edge

Does any know what the vacuum line in the upper right of this engine is for? Is it not supposed to connect to anything?

Note: this is not my engine, mine is in the car, found the image online from speedriven

Dr Matt

Nope, doesn't go anywhere. It's just plugged off on my car too. I have no idea what it is for.

MooksM275

That line is a test port for the vacuum system. I don't have the exact procedures in front of me, but it is used to test whether there are any vacuum leaks and can be used to test the function of the electronic valves.

I read about the function of this in WIS I believe.
Cheers

r_martin126

The vacuum port on the right intercooler is for the wastegates for the turbos.

Welwynnick

I doubt it. The waste-gates are actuated by compressed air, and the diverter valves are actuated by vacuum.


Nick

r_martin126

Nick I dont care what doubt you have because I know without a shadow of a doubt the nipple that comes off the back of the right intercooler is the pressure line for the wastegates!

The intercooler has compressed air in it during an in boost situation! Thus the pressure (compressed air) from the intercooler is routed to the wastegates for the turbocharger. The bypass valves get vacuum from the vacuum reservoir under the intake manifold which gets vacuum from the intake manifold itself from a nipple of the back of the intake manifold. I own a SL600 and have more hours under the hood of it to count.

Welwynnick

Agreed. I thought you were talking about the vacuum port that the original post referred to.

Obviously, the vacuum connection has to come from downstream of the throttle.

Nick

syljua

I would think that this is the vacuum test connector "B" for the Divert Air Control system.

Read about it in page 68, here;
https://web.archive.org/web/20060508...2008-06-03.pdf

Divert Air Control system purpose is to reduce charge pressure when throttle is released.

My thoughts;
It looks more or less like the same system as wastegate but this time to bypass
the compressor wheel (as opposed to bypass the turbine wheel of the exhaust part
that the wastegate does). And, while the wastegate can be in a partially open/closed
state, the Air Divert will be either on or off?

br,
syljua

biker349

syljua, that manual is a great find! thank you for sharing!!!!!