When there is a problem in the vent system it defaults to defrost setting. Check the doors & vac supply
that usually indicates a vacuum leak which causes the system to go into default mode, which is defrost.
If the temperature cannot be changed for any of the direction settings, e.g., defrost, vents, floor, then the problem is very likely to be the blend door actuator motor.See "Related Questions" below for more
If the vents stop blowing when gas is applied, it is likely a vacuum problem. The vent system is controlled by vacuum, so when the engine is under load, there isn't enough vacuum to run the vents. How you test this is when the problem occurs, the fan will still be blowing air, however the flow of air will be out your window defrost vents at the top front of the dash. On a 1995 vehicle, it's likely just some of your vacuum lines are broken, and need replaced or repaired.
If this is the condenser that is frozen, you have a problem with the defrost cycle. There are 2 things that need to be checked, the defrost sensor and the defrost control board. More than likely it is the defrost control board that is the problem and of course that is the more costly of the 2.
Where the air blows out control are vacuum operated.A more common problem is when the air is stuck on defrost only.The cause is essentially the same, so check out the "Related Question" below for where to go next
Hi, I had this problem on a 2000 Alero. Had to disconnect the battery to shut it up. G.M. replaced the horn relay to aleviate the problem. Duke
Found problem, intermittent short circuit problem in turn signal switch, replaced switch, problem went away.
If you can Not change the location of the air flow to the different outlets (defrost, dash, floor, etc) That sounds like a mode door problem or a mode door control knob.
Dodges are good for blowing fuses. If that is not it, the fan switch might need replaced.
Hi have same problem my Montero 2001 serial 99F60514 model MR563520
Cannot tell from the question if the problem is:Air is not blowing at allAir will not come out the dashboard vents, versus defrost or floor directional settingsSee "Related Questions" below for coverage of both