Heaating/ac Vent Problem-1993
Thread Starter
7th Gear
Joined: Oct 2007
Posts: 7
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Heaating/ac Vent Problem-1993
My heater and ac work fine but will not discharge air through center dash vents. The air discharges through the windshield defrost vent regardless of blower control setting. It causes the front windshield to have condensation in summer and slow to warm car in the winter. Is this a problem with the heater/ac programmer? Any help would be greatly appreciated.
Thread Starter
7th Gear
Joined: Oct 2007
Posts: 7
Likes: 0
Heating/ac Vent Ducting Problem
Where is the fuel rail located? I thought that the problem might be with the ac programmer which is located under the LH dash panel just to the right of the steering column. One of the air distribution valves is obviously not opening/closing and all the air is being channeled up through the defrost vent. I believe the problem is either a vacuum leak or a bad electrical board in the programmer. Would a bad electrical board cause this problem?
Instructor
Joined: Dec 2004
Posts: 231
Likes: 0
Where is the fuel rail located? I thought that the problem might be with the ac programmer which is located under the LH dash panel just to the right of the steering column. One of the air distribution valves is obviously not opening/closing and all the air is being channeled up through the defrost vent. I believe the problem is either a vacuum leak or a bad electrical board in the programmer. Would a bad electrical board cause this problem?
Drifting
Joined: Oct 2005
Posts: 1,257
Likes: 4
From: North Carolina
I don't mean to hi-jack the thread, but this is an issue that has been haunting me for a year now. The heat blows ALL THE TIME,... and you can't control the vents. I was under the impression that everything was electrically controlled?? Does this apply to an 89 Vette?
DG
DG
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Racer
Joined: Dec 2004
Posts: 470
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From: Phoenix Arizona
Above is the link and I also attached a picture
Hope this helps....................
Thread Starter
7th Gear
Joined: Oct 2007
Posts: 7
Likes: 0
Heater/ac Vent Duct Problem
Your corvette is the VIN J configuration versus mine which is the VIN P configuration. The vacuum routing and system is different for these two different VIN configurations. I do not have a check valve but rather a "T splitter." One end of the T goes to a conduit and back to the vacuum tank. The other end of the T goes to the cruise control servo. The third end of the T is supposed to go to the vacuum source but I can't locate it. The third end of my T is attached to a 15 inch vacuum hose that has come loose and I can't locate the vacuum port that it connects to. The service manual (1B-39, fig. 34) isn't clear showing the routing of this 3rd vacuum.
Could someone who has a 1993 Corvette with LT1 engine and VIN P configuration look under their hood and tell me where this 3rd vacuum hose coming off the T splitter goes to?
Could someone who has a 1993 Corvette with LT1 engine and VIN P configuration look under their hood and tell me where this 3rd vacuum hose coming off the T splitter goes to?
Thread Starter
7th Gear
Joined: Oct 2007
Posts: 7
Likes: 0
Heater/ac Vent Duct Problem
Yes, I am stupid. I finally located the check valve and replaced it as suggest by several members of this forum. Magically, my vent problem is solved! For $3.50 and the help of several forum members, I have resolved a problem that has driven me crazy for over 2 years!It turns out that the disconnected vacuum line on the drivers side that I discovered is a completely separate problem associated with my cruise control. However, I can live without the cruise control.
Thank you so much!
