Heater core replacement
My 1994 Buick Roadmaster blows cold air great but not hot air. I replaced the thermostat but still no heat. Is this likely the heater core? Where is it located on this car? Thanks in advance for any help.
Tom Gibbs
Cars & Trucks - Buick - Roadmaster - 1994 Buick Roadmaster
Answers & Comments
How do i change the stereo on my 1995 buick roadmaster?
There is a air bleed valve on the side of the thermostat housing.make sure the system has been bleed of air or you won't have heat either.
I talked with my cousin who knows vehicles and has extensive knowledge in electrical systems ( he deals with them on daily basis in his trade) . After speaking with him, reading info from Chilton's manual, and talking it over with some help full guys at Napa, the problem is leaning towards the actual digital control unit we see in our car. Something in the circuitry isn't making that connection telling the various rheostats or diodes or whatever diverting the coolant to the heater core while bypassing the a/c equipment ( or something like that). I am going to dive into my dash and pull the Temp. control unit out to see if it is something like a loose or burnt wire. However, I know by looking at the schematics of the wiring diagram that there are pressure switches and other things involved, so I'm not ready to ask Buick how much a whole new digital controller costs just yet. A possibility is to find one at a bone yard for a much cheaper price. Swap it out and see if anything happens. At least I won't be paying for a full price controller, because god knows what buick will want for it. If it works great, if not then I know to start looking into those pressure switches or rheostats or what have you.
If you decide to try the same your self be aware that the air bag system needs to be deactivated before you go digging into the unknown. There is an air bag fuse that needs to pulled and two wire harnesses that need to be disconnected. One for the drivers bag and one for the passengers. Disconnecting the battery ( which Chilton's instructs doing) I don't think will be enough. Those
connections might have constant power even with the vehicle turned of, in case of any impacts that arise from that situation.
I will try to keep you informed on my progress at my end. If you like you can contact me directly
at [email protected] . Maybe we can this solved before our windshields start icing over.
I had the same problem or still do. I disconnected the wires to the air dryer which stopped the compressor. That did solve the cold air problem and with a flush of the heater core I have warm air now. It is a quick fix till I can determine why the a/c wants to keep running