before i start , let me inform you guys my ambient air temp display is still stuck on 140! (i am going to replace it this weekend)
the only reason i am asking for help with the heater is because is was not working before the ambient air temp sensor went bad. soo.....

when i am checking for problems with the heater, here is what i have gathered:
1. Coolant level is fine (I fixed the leaks when i changed the lim gaskets and elbows)
2. Inlet and outlet heater core hoses are hot after engine is warm.
3.The thermostat is working (BTW is a 195F stat, 180 for summer)

i know there are air mix actuators that could be malfunctioning. how do i go about making sure they are working? also, could the air inlet actuator cause the problem? if so how would i test to see if it is working properly? what else should i check if these actuator are working?

[quote="kaziouz"]before i start , let me inform you guys my ambient air temp display is still stuck on 140! (i am going to replace it this weekend)
the only reason i am asking for help with the heater is because is was not working before the ambient air temp sensor went bad. soo.....
quote]

Are you saying the ambient temperature sensor in front of the radiator is bad? If so if it'* reading high that would keep the unit from giving as much heat unless you put it on 90 degrees.

Have you tried removing and reconnecting the temperature sensor? Those contacts often give trouble.

Or you might remove and operate without it to see if the default reading for ambient temperature will let the air vanes give more heat.

yes, the sensor is bad. i unplugged it, gave it a couple of seconds, plugged it back in and the temp was accurate again (it was about 50F outside and that is what the display said) after a couple of minutes of driving i noticed the temp was up around 140F again. i checked all of the connections and they were good and clean.

also, i do have the temp set to 90F, and its still a little cool.

i never thought to just run without the sensor. i would expect the hvac to go crazy without it, right? i'll try to run without the sensor and see what i get.

any other suggestions are appreciated!

i had poor heat in my buick. i recently had the heater hoses off, so i just pressed the garden hose right up to em. for a "flush". that made a world of difference.

If your airmix actuator was bad, it would be flashing the temp display to indicate an error.

Do you have full fan function? Does it blow alot of air inside, just not warm enough? If so, inspect your radiator core by looking inside through the cap hole with a flashlight. Any sludge? If so, the same may be true of the heater core.

If the airflow itself seems low, try the evap cleaning procedure in Techinfo. Bear in mind that the procedure was written for 97-99'*, and yours is quite different.

I don't think this one is going to be an electrical problem, but we'll let it shake out here first.

well, running without the ambient air temp really didnt help any, so no luck there.

i was unaware the airmix actuators would cause an error to be displayed. (what the heck wont these cars report?!?) i dont have any flashing lights (although the ses light is on, but i think that has to do with the cat).

It blows tons of air inside. i just need it to be a lot warmer! i've got a little boy, and a pregnant wife, and she REALLY wants it to be warmer!

i'll take a look into the radiator and see what i come up with. even if i dont see any sludge in there, i think im still gonna flush out the heater core. is there anything special i should know before i try that, or is it just put the water hose in the heater hose and blast away?

As far as the "flashing lights" are concerned, what you are looking for is if your "temp" display/readout flashes on start-up. Whether it is reading 140* or 0* (or anywhere in between), if it flashes upon start-up of the car, that indicates a fault and will help us know if you have a problem in the HVAC system itself. You may also have a radiator/heater hose/heater core issue, but if your display flashes, I would suspect the actuator of the external temp sensor is the culprit.

I am assuming you have "AUTO" climate control? Does this occur in both "AUTO" and manual modes?

yes, i do have "auto" climate control and the issue occurs in both auto and manual mode. i've looked at the display when i start the car, and its not flashing, so i guess this really isnt a problem with anything electrical. (sorry for posting in the wrong forum ) so you think flushing the heater core should help? should i get some solvent to help remove debris?

thanks guys.

On the 2000 Hyundai it did the same thing. The cold/hot **** was cable actuated. And it wasn't opening it all the way to the hot. I dunno if the Bonnevilles have the same set-up or not but worth a try, unless it'* all electrical.

Ok, this does seem rather odd. If you have hot heater core hoses, and the airmix door is functioning properly, you should be getting hot air :?

My experience is limited to the 92-99 Bonne, and maybe there is something in the 2000+ that is different that I just don't know about. Maybe the 2000+ display doesn't flash if a problem exists like it does in earlier years. In the 92-99, the door is COMPLETELY electronically controlled by the HVAC programmer. Even if the temp sensors were not working, by manually commanding heat, you should get hot air unless the airmix door is not functional.

Does anyone know if the system changed for 2000+ or is it basically the same system?

If it is the same, is it still possible to look through the hole behind the glovebox and watch the airmix actuator arm move the door?