1989 C1500 5.7L vacuum routing diagrams

[Muskratt2]

Can someone post a vacuum hose wiring diagram. I am having an issue with my cruise control not working & the vents are not working on my A/C. I was told by a mechanic that this would be caused by a vacuum issue.
I found a fitting on the square box beside the TBI is missing a hose. I am figuring this is the issue.

 

[someotherguy]

On an '89 C1500 vacuum has absolutely zip to do with either of those systems. The cruise is run by an electric stepper motor and the actuators on the A/C system are electric too.

There is an EGR solenoid on the passenger side of the TBI that should have a single open port that is a vent, this may be what you're looking at.

Richard

 

[Muskratt2]

Thanks Richard. I will check that out.
This also probably explains why I couldn't find where it went.