Mechanics

FRONT DRIVE AXLE VACUUM ACTUATOR SOLENOID VALVE?

2000 GMC Jimmy • 170,000 miles

I have a 2000 GMC Jimmy 4X4 The Vacuum Actuator Solenoid Valve hoses are disconnected and dry rotted. I can not find a diagram where these hoses go. Can anyone please help. There is a picture of the solenoid valve in the link below.
AD
Avatar
Justin Adair
September 26, 2011.




The solenoid passes vacuum when it is energized, or when the vehicle is in 4-wheel drive mode. The driver side hose supplies engine vacuum to the solenoid. From there it should go to the transfer case.


Rivermikerat
Sep 26, 2011.
Is it possible that the vacuum hose from the solenoid sends vacum to the front axle when switched? The switch on the transfercase is moved when the transfer case is shifted.


If the vacuum hoses are not installed correctly, the vacuum would not release when the switch is turned off. The manifold vacuum hose should be connected to the outer port of the solenoid.
AD


KHLow2008
Sep 26, 2011.
Okay the hose that comes out from the manifoldconnects to the top T as displayed in the pictures then the hose directly across goes somewhere on the drivers side. On the lower t that is where the solenoid hooks up. Now as for the hose from the solenoid to the driver side it as hanging by the battery against the engine dry rotted and wasnt connected to anything. If I had a diagram or knew where exactly the hoses went I would be home free.


Tiny
Justin Adair
Sep 26, 2011.
Ok. On one side of the vacuum "T", you have vacuum going to the AC/heater controls and to the front axle. The other side is vacuum supply from the manifold. I have found a couple of other images that may be easier to see.


Rivermikerat
Sep 27, 2011.
"The a/c controls and front axle actuator are vacuum actuated and both use the same vacuum source."
"Check the vacuum hose coming from the engine and the vacuum hoses around the vacuum reservoir, located near the drivers side hood hinge. This is the most common point of failure."

Here's a couple more vacuum diagrams.


Rivermikerat
Sep 27, 2011.
Yeah the diagrams of the hoses and axle above that you have are wrong. We obtained a copy from a dealership that luckily had one. We found the hose that leads to the passanger side and are still looking for the area for the driver side. I believe it goes into a canister like you said but can not locate it.


Tiny
Justin Adair
Sep 27, 2011.
There should be a small metal flap, behind which the vacuum reservoir/amplifier is hidden. In the driver side fender.


Rivermikerat
Sep 28, 2011.
Okay I located the connection for the other hose on the driver side. In the last picture I uploaded it is Item 10 and is located behind the box where the brake lines go. It is well hidden on the driver side about the wheel well and in the middle of the fender as described. Now my proble is I am getting a random misfire Code 300. I have changed the plugs, wires, distributor and fuel filter. The vehicle sometimes bogs down when I hit the gas when I first start it (Seldomly while I am stopped at a light or so on). But most of the time it runs normal? Tried LUCAS injector cleaner aswell.


Tiny
Justin Adair
Sep 29, 2011.
I prefer Techron, but I have 30 years' affiliation with Chevron, so that may explain that. If you have an OBDII scanner that can gather real-time data, clear the code and see what data can be obtained in real-time. You may have a problem with the ignition module or a sensor/pickup somewhere.


Rivermikerat
Sep 29, 2011.

AD