I just replaced my VP44 and when I took my truck for a test drive I found two more problems

My cruise control will turn on but will not actuate.


My heater works but wont change from the defroster position regardless of my choice!


I cant find fuses for either of these systems, does anybody have any helpful information?

 

My guess is that while you were working on your VP you pulled loose your vacuum line from your vac pump. The reason I know this is because I did the same thing. Those two poblems both run off the vac pump. Should be a stiff plastic tube which plugs into a rubber tube at the pump.

 

Yep, second the vacuum line. Just swapped my heater core and I had accidently messed up a vac line.....only defrost and nothing else. Quick fix, just replug and play....LOL. Good luck with it.

 

same here ,only industrial injection did it..... easy fix

 

The hard plastic line can be brittle. Mine broke in a couple places. Rubber vacuum line from autoparts store spliced the pieces together.

 

Yep I did the exact same thing!!

 

I have the same issue but with a p-pump truck, where would I find the vac line for that?

 

Same place. The vacuum pump is in front of the PS pump. There is a port on the side of it. Just trace the hose from there to the places it goes, e.g. cruise control actuator, under the left battery, and the HVAC plumbing, which enters the firewall directly above the exhaust manifold. If you have a 96 or older truck, you also have a brake booster and a vacuum sensor for the bakes on the left fender well.

Chris