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Took a nice cruise to Lancaster, PA with my vette club this weekend that included a driving tour of Gettysburg. While driving around the battlefield, I noticed that the A/C was not workinh up to par. The blower seemed weak, even on high. Felt the vents and noticed that the defrost was blowing, even in the off position and when I turned on the defrost, there was no change.
I assume the problem is with the vent duct doors. How are these controlled and what are some common problems/solutions?
Doug
Hi, the modes are controled by vacuum which starts at the fitting on the back of the intake manifold, a vacuum line connects to the L shaped fitting and runs through the wiring harness over to the vacuum tank check valve on the pass side under the battery box, then through the firewall to the vacuum block in the pass side dash behind the glove box, and then to the controll head.
The first place to look is under the battery box for acid damage that may have burned through the vacuum line, then see if the line came loose from the intake manifold fitting. If none of those are the problem , you have to look at the vacuum block inside the car and the controll head for a problem
Good Luck