Heat - 96 Bonneville SE

[jmulhearn]

I recently received a 96 Bonneville SE, 235K. Have one real problem:
Heat: I have the electronic control panel.
The user manual says that it takes 20 min to adjust to the inside temp. ?? Is it really supposed to be cold for more than 3-4 min when starting the first time?
My car sometimes gives me some heat after 3-4 miles but when I stop for coffee for 5 min, it's always cold when I start it up after I come back. Very confusing, after I am driving for 10-15 miles I may get heat but it seems just a matter of luck. If I am sometimes getting heat, does that mean that my heater core is OK and the problem is probably the air-mix control?
Also: The user manual says there are two sensors for temp control inside the car. Are these the two things on the top of the dash board (one in the middle of theone problem dashboard, against the windshield and the 2nd one even with the steering wheel about the center of the distance between the window and the edge of the dashboard). And, can I/should I clean these if they are?

I have always had GM cars, usually Chevy and am not going to change now. But I'd like to find out how/why this Airmix control gets broken because you have to change your battery.

One last thing: I have always wanted power windows and cruise control. Well, I finally have them on this car and they both work fine (but I had to replace the battery, belt tensioner, brake line, fuel lines and some emission control items). But, those things come with age. I am just stumped with this heat problem.

Thanks for any help. I just found this site a couple of days ago and have been reading what i can but there is so much information here it is difficult to sort out just what applies to me.

[smokey13]

jmulhearn - in my estimation, the gentlemen or gentlewomen you need to have read your post have not found your post because they are old hands on this site and seldom look at the "Introductions for new members" when they enter this site. I'm trying to politely tell that you need to move your question to the "Mechanical and Maintenance" section of this site.

You may need to go to the Index page, find Menu box, scroll down to the Mechanical and Maintenance section, scroll down a little further until you see "1992-1999" heading and post the same post/question there.

You may indeed have a malfunctioning air control valve as you suspect. It is located behind the glove box area and mounted on the ductwork; the glove box would have to be removed to see if it is operating/moving back and forth as you go from the highest temperature on the digital display control box to the coldest temperature. If it is working you will need further help from others as that is the limit of my knowledge of this particular problem.