Let us know if the flush fixes your problem. I have same thing going on with 94 STS, but just the opposite side. My drivers side footwell area has no heat, but passenger side does. I am not able to flush due to a ThermaGasket additive in my coolant that needs to stay there for another 200 miles. So watching for your results.CAD4DAD said:i have a 96 sts and the heater only blows out hot on 1 side of the car the drivers side, the passenger side blows out cold. this happens when i use the defroster also. what would cause this? and how do i fix it?
JPL189 said:If you are getting heat on one side, it is not likely the heater core, since the heater core is not separated into sides. It is more likely something in the HVAC controls.
I read through a ton of messages on here about this same thing. They are indicating the flushing is successfull on 93 and later models. Those years did not have a seperate vent ducting at the bottom. From 94 they put in the lower air controls at footwell.Trench said:I could be wrong, but I swear I've read several threads on a half clogged heater core causing this exact issue. Recall reading up that Drain-O may be worth a shot.
.Ranger said:Sounds like Thermagasket clogged the heater core.