Question about 1999 GMC Safari
My a/c iis coming out of the front defroster and I cant switch it to the other settings. I found a vacuum line lose near the firewall.
Vacuum hose over top of engine attaches to vacuum outlet port on intake manifold by pcv outlet port. this line is vacuum supply to heater controls.
Posted on Jul 10, 2009
I tried to give you a vaccum diagram but the manufacture will not release that info to outsiders. you need to find where the hose goes to.if you loose vac to the controls it goes to defrost mode.
Posted on May 27, 2009
Have a 96 safari had same problem, has hard plastic tube running and laying all over the motor got hot and brittle kept breaking. tracked it down to other side of engine used rubber vacume line to splice the good ends and routed so as not to lay on the motor
Posted on Jul 02, 2009
Most common problem is the vacuum line broken off at the rear of the intake .you will need to take the doghouse off to get to it ,other common issues is the vacuum ball below the right lwr side of the radiator is cracked or line has broken there older vans are bad for the plastic lines cracking in the loom that runs across the engine compartment you can trace it back fron the heater control valve on top of the heater core/evaporator, I have found that they also split at the firewall behind the battery .Here is a Safari Vacuum line diagram from the controller out under the dash .Hope this helps you .
Posted on Aug 08, 2009
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
Sep 19, 2015 | GMC Cars & Trucks
Jan 28, 2014 | 1998 Holden VT Commodore
Nov 15, 2012 | 1998 Chevrolet Tracker
May 28, 2012 | 1997 Ford Ranger SuperCab
Aug 11, 2010 | 1997 Ford Expedition
Dec 20, 2009 | 1997 Chevrolet Lumina
Jul 01, 2009 | 2002 Jeep Wrangler
Jun 19, 2009 | 1999 Cadillac DeVille
May 27, 2009 | 1999 GMC Safari
881 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: