Okay, sorry for creating a post on possibly an already answered problem, but I haven't found anything that can exactly match the problem I'm experiencing right now.
A while ago, I had a battery terminal problem that caused my car'* power to go in/out a several times. After getting this fixed, the ECC temp started blinking. I had the error code read and it said that the HVAC didn't have enough power (a possible vaccuum leak within the unit). The guys at the GM dealership said it was contained in the HVAC unit itself. The A/C often comes out hot, the heater often comes out cold...the various vent modes work okay for the most part, but it does often not fully flow from one single vent mode, and the A/C gets stuck in the top defrost vents (though it has always started coming out from those vents back when it worked). For a while the error was gone, and the system worked flawlessly, but after having the power disconnected again, the error came back and so did the problem. Fiddling with the controls from hot to cold, recirc off and on, can sometimes make it switch to the proper setting. The guys at the dealership said it worked when they jiggled the unit around a bit. I haven't gotten it checked since the 1st time it occured.
Even more info: I noticed that it usually starts coming out hot, and then a thud, then cold air. Please help with a very cheap solution. chr0mius is a poor boy.
Also, the person that helps me fix this can win 1 free internet.*
*Not valid in Alaska, Hawaii,the District of Columbia, the 48 contiguous United States, Canada, Mexico, or Western European nations.
1997 Pontiac Grand Prix GT, mod list: CAI, more to come...
Sound: Kenwood X889 w/ 800 watt amp. Boston SL95'* rear, SX50'* front.
Appearance: Short antenna, projector headlights, custom grills