Heater problem
Thread Starter
6th Gear
Joined: Dec 2011
Posts: 6
Likes: 0
From: centra valley utah
Heater problem
Just bought a 1987 vette and allready have a problem.Heater sometimes blows hot air then if i shut engine off sometimes it will only blow cold. Anybody know what would cause it?.Thanks, Sheprzr
Instructor
Joined: Dec 2011
Posts: 105
Likes: 0
From: El Paso TX
I have the same problem, as do many here. It is most likely the blend door not closing properly, mine flutters and tries to close but does not fully close. I closed mine by removing the relay and pushing the door closed with a long stick. For the exact location and some pictures do a search of heater, blend door etc and there are several posts to help you out.
Thread Starter
6th Gear
Joined: Dec 2011
Posts: 6
Likes: 0
From: centra valley utah
I have the same problem, as do many here. It is most likely the blend door not closing properly, mine flutters and tries to close but does not fully close. I closed mine by removing the relay and pushing the door closed with a long stick. For the exact location and some pictures do a search of heater, blend door etc and there are several posts to help you out.
Racer
Joined: Oct 2011
Posts: 392
Likes: 6
From: woodstock ga
mine did the same thing. after repacing the air blend door actuator, the controller and extesive research on this forum i discovered the programmer was the problem. it is under the drivers side dash and hard to get to but worth the effort. any tv/radio repair shop can resolder for less than $10. call me if you need help 770 235 5257.
Thread Starter
6th Gear
Joined: Dec 2011
Posts: 6
Likes: 0
From: centra valley utah
mine did the same thing. after repacing the air blend door actuator, the controller and extesive research on this forum i discovered the programmer was the problem. it is under the drivers side dash and hard to get to but worth the effort. any tv/radio repair shop can resolder for less than $10. call me if you need help 770 235 5257.
Racer
Joined: Oct 2011
Posts: 392
Likes: 6
From: woodstock ga
Sheprzr
check out these two post, good instructions and pictures.
http://forums.corvetteforum.com/c4-g...d-removal.html
http://forums.corvetteforum.com/c4-g...king-help.html
check out these two post, good instructions and pictures.
http://forums.corvetteforum.com/c4-g...d-removal.html
http://forums.corvetteforum.com/c4-g...king-help.html
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Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
These symptoms sound like bad solder connections on the HVAC programmer PC board. The HVAC programmer is located right above the accelerator pedal. Two large resistors feed voltage to the temperature door motor. They get very hot and cause the solder connections to go bad. They are shown in this picture (lower left corner -- note heat discoloration on PC board):
The HVAC programmer is held in place by one 7mm screw (tab in lower left corner of the pic). You also need to remove the press on clip buried among the vacuum hoses on the back. I replaced mine with a nut.
The HVAC programmer is held in place by one 7mm screw (tab in lower left corner of the pic). You also need to remove the press on clip buried among the vacuum hoses on the back. I replaced mine with a nut.