New answers tagged


On the 97 Sonoma the controls are electronic and send a signal to a vacuum switch block which will send vacuum to various valves. This is from a corvette but is similar. While the switches on the control panel can fail more commonly the vacuum lines, check valve or vacuum reservoir will fail first. Locate the vacuum source line and measure engine ...


Heck yeah! Short answer: Replace the check valve. Long answer: There is a check valve between the vacuum reservoir and the rest of the system. What that does is help the vacuum reservoir hold more vacuum. Your engine won't have enough vacuum "force" to move the heating ventilation doors without the reservoir. The check valve is that little black and ...


with the car running, use an aerosol can of carb cleaner with the straw in it to spray around the vacuum lines and fittings. When you get to the leak point you will hear the rpm change. move slowly and use spurts.

Top 50 recent answers are included