Cold Feet

[Devilinblu]

I own a 2001 S-10 Crew Cab Pick-Up and a 2004 S-10 Blazer.

Last month, all of the heat in the pick-up started coming out of the defroster vents instead of the heat vent.

I took the truck to my local Chevrolet dealer and had them check the problem.

I was informed that the vacuum actuator that opens the damper to the floor ducts had sprung a vacuum leak, which had sucked moisture into the vacuum lines going to the selector switch, ruining the lines and the selector switch. The result was, the vacuum actuator, the selector switch, and the vacuum lines (still can not figure out why you would have to replace the vacuum lines instead of blowing them out) needed to be replaced according to the mechanic, for a cost of $355.00 in parts, plus 2 hours labor at $69.00 per hour to replace them. ($493.00 + tax).


Needless to say I almost fell over and left without getting the problem fixed.

Last week, the Blazer developed the exact same problem.

My question is, where is the vacuum actuator located? I have found one behind the glove compartment. Is this the one that needs replacing or is there another that I did not see? The dealer’s mechanic would not allow me to watch as him, saying it was against insurance regulations to have customers in the shop area, while he was checking my truck so I am not sure where it is located.

I intend to replace just the vacuum actuator first and see if that solves the problem.

[old_master]

The HVAC system will default to defrost, (on both of your vehicles), when the system loses vacuum. From under the hood, locate the 1/8" black vacuum line running from the engine to the bulkhead, (firewall). Make sure it is not broken, and has a strong vacuum when the engine is running.

[Devilinblu]

I am getting vacuum. I found a block of several vacuum lines near the actuator, unplugged them, and got a strong vaccum there, the air started coming out of the AC vents, plugged them back up and it diverted back to the defrost duct.