VIS Vaccum line

[Bashir]

Please help me identify where the short vaccum pipe from the VIS in my 1997 Ford Explorer V6 goes. It is hanging and I cannot find where it should go. I have very poor gas mileage (5km/l) and read in other parts of the forum that this can be caused by vaccum leak. My search under the hood identified the above pipe. Thanks.

 

[drdoom]

Bashir which end are you referring to, the VIS side or the other end? Reason I ask is I have the same truck, could take a peek if that would help you. Because I know that under the plastic intake cover there is the VIS and the vacuum line plugs into the back of that. I would have to look and see if I could find the other end. I do recall it is a small vacuum line, at the rear of engine near firewall. I have vac diagrams on another computer also.

 

[Bashir]

Thanks drdoom. It is the line that enters the rear of the VIS. The small piece from the VIS is there but I can't find where it should fit. I will appreciate if you can check out your truck. Thanks.

 

[drdoom]

Bashir I am looking into it right now. I have some photos maybe.

 

[drdoom]

With the cover removed, you should see the vacuum servo for the VIS. Notice that on the rear of the servo is the vacuum port. The vacuum line has a rubber fitting, which slips onto the VIS vacuum servo inlet (reach your fingers behind there and you'll feel it). From there it should run back around the right side of the intake (your left when standing at the radiator) and attach to the vacuum solenoid assembly.

 

[koda2000]

I've never heard of this part. What the heck is a VIS?

 

[drdoom]

Koda on a 97 SOHC there is a Variable Intake System which changes the length of the plenum runners above 3000 rpm or so. A butterfly plate of some sort, controlled by the vacuum servo.

 

[koda2000]

Koda on a 97 SOHC there is a Variable Intake System which changes the length of the plenum runners above 3000 rpm or so. A butterfly plate of some sort, controlled by the vacuum servo.

Ahhh, Good to know. I'm familiar with the concept - Thanks.

 

[ThatNGuy]

I believe there is a vacuum solenoid on the passenger side of the engine. It will be sitting on a bracket. IIRC, there is a vacuum canister under the upper intake, line goes to the solenoid, then to the vis.