Ok, maybe I am? I was talking about the electic actuator door, above the programmer. What door are you talking about and where is it located and how do I check it?

I drove it today, and both hoses going to the heater core were hot. I could hold for about 3 seconds and it was too hot. Is that good? I dont have an infrared thermometer.

Skin test works fine. That just means the coolant is hot going in and hot coming out. Which ALSO means, 1 of 2 things. The external side of the heater core is plugged(leaves and crap) or 2, the vent isn't working correctly to pull hot air through the core.

I have searched my Alldata subscription(97bonneville) and I cannot find a diagram of the actual system, but did find (instructions to remove it) but they were vague and read like stereo instructions.

But I did find a the proper terminology of the item in question...do a google/image search of this...
bonneville A/C Temperature Valve Actuator. You will see images for the 92-2005 series. But it will at least give you an idea of what to look for under the dash. I know somewhere here on this forum people have done it a hundred times.

How would leaves and crap get in the fins of the heater core? Isn't that inside the car? If not, how do I get to that thing to check it?

I googled that, and it comes up with a million pics of the actuator I was talking about too. That works great, I already verified that.

I guess that last thing is seeing of the heater core is clear of debris. I just need help getting to it to inspect it

You'd be surprised at how stuff gets in there.

I could have sworn we had a write up somewhere in here. It involves removing the blower motor, and blower resistor so you can gain access to the environment side of the heater core, and shooting cleaning agents into the core. It involves getting your garden hose out too.

hmm, if it involves the garden hose, I cant do that then. Up in MN we are not getting anywhere even close to the freezing mark, we are well below. :(

Any other ideas then?

None really. Only option would be indoor garage. But until we can fully determine if its the door or the core itself, we would still be guessing.

ok. Well, how do I dig into the core? I can inspect it without using water.. as the water would just freeze and make a hell of a big mess! hahaha

Pull the blower motor resistor. You can peek down in there and see the core. Matter of factly, you might be able to sneak a vac hose down in there and suck whatever out.

How about an alternate approach...you may want to do a pressure test, and that your LIM gasket could be failing. I know you replaced it in 2009, but I sense that may be the issue. Not getting up to proper running temperature in the winter points me to a LIM gasket failure, although logic says t-stat. T-stat replacement will often mask the LIM failing for a few days after replacement, I have no idea why.

To flush your heater core in the winter- go to a car wash with a high pressure hose, use the lowest setting and the flush will go just fine. You will be wet, cold and miserable, but it works. I flushed a Bravada core in the winter at a car wash when I did not have a garden hose available, found it to be pretty easy to do at the car wash.

thanks guys. Another thing I wanted to add, when I first start the car cold, and turn on the heater, it squeals really loudly for about the first minute to two minutes. I dont think it is the blower motor, because the squeal doesn't change with the fan setting. But, it does sound like it is coming from the middle of the car. I know without hearing it for yourself you would think blower motor, but because the pitch doesn't change with the fan speed changing, it leads me to think it is something else? Any idea what it could be other than the blower motor?