my air mix doors WORK properly. i can watch the actuators move the doors. both of them have full travel with no problems! i can disconnect the actuators and move both doors by hand. the driver side air mix door will make the air VERY cold....or at "full hot" it will allow a slight amount of heat through...not enough to call heat though, just enough to say "not freezing"

i'm not sure if it has anything to do with the dual climate control or not. but i do plan on ripping this car apart this weekend! if i have to take the entire dash apart until i see bare sheetmetal i will do just that! i'm thinking it is a very similar problem to the bonnevilles even though they didn't have dual climate control...

this whole situation just seems....well impossible! i wouldn't believe it if it wasn't happening to me! i can't believe nobody knows the solution!! :( ...YET

You do realize there are not seperate air mix doors for the driver and passenger sides. That is where we are having the trouble diagnosing and coming up with a solution.

in the bonneville there is NOT a separate air mix door. but in my PARK AVENUE there are in fact separate air mix doors for pass/driver, BUT i don't even feel heat getting to the other side of that door...so the problem is before the mix door!!!! SO....i'm guessing the problem is the same exact thing that'* wrong with the bonnevilles. since it'* not my air mix door... i'm hoping it'* the same problem anyway, that way we'll all know by the end of the weekend. why couldn't i find this problem when it was warm out!!!! what a pain!

Ahhh sorry. I forgot you had a non bonne. Also looking at if from the original post. Thanks for setting me straight.

Hope we can get everyone fixed up and feeling the warmth.

Not sure our terminology is straight here. In the dual control system in Buicks and Oldsmobiles, the air mix valves are after the heater core, one for passenger and one for driver. In the Bonneville, the single air mix door is after the evaporator and before the heater core. If you were able to get your hand on either side of it, it would be cold.

Here are the flow schematics from the '95 FSM for dual and single systems:



DUAL SYSTEM ABOVE



SINGLE SYSTEM ABOVE

You don't suppose it is possible that somehow these guys have the dual system installed in their cars? The dual system was only supposed to be available in Buicks and Oldsmobiles. The hot right, cold left is a common mix door problem on the dual system.

I hope I got these right. (Maybe someone can double check me?)

If you guys with the hot pass / cold driver problem could check the sticker on the spare tire cover and determine which of the following RPO codes you find for your A/C system. That would confirm a factory installation of CJ2.

RPO codes are as follows: Automatic Electronic A/C....C68
.................................................. Dual Zone A/C......................CJ2
.................................................. .Manual A/C...........................C61
.................................................. .Electronic A/C......................C67

If someone changed out the original for a dual control system, (if that is possible) you should be able to determine by examining the heater housing.

Good morning!

I took some temperatures and did some experimenting last night and this morning. I used the outdoor sensor (wired) of an indoor/outdoor digital thermometer that I've had a couple of years and know to be fairly accurate.

The temperature in the garage and the car before cranking last night was 44* as indicated by this thermometer and another one that I placed alongside of it for verification. The coolant temp gauge stayed at an estimated 140* to 150* during all tests.

I placed the sensor in the inside drivers dash vent (toward the center of the dash), cranked the car, and let it warm up while driving. Took several measurements as the thermometer climbed a bit and then stabilized, maxxed out at 58*. Trust me, this 58* felt freezing while blowing on the hands. Contrary to what I wrote last night, there does appear to be at least a slight mixing of air somewhere, or the temperature would have stayed at 44*. I couldn't 'feel' much difference though.

Moved the sensor to the inside passenger vent where hot air was blowing out. It quickly rose to 95*, paused there momentarily then climbed up to 101. Following the suggestion from an earlier post, I closed the driver side vents to see if it might force a mix, but it had no affect on the temp. It stayed at 100-101.

Moved the sensor to the passenger side defrost vent. 101*. Moved it to the driver side defrost vent. 89*. Huh? Opened the driver dash vent and felt the air. Still 'freezing'.

Ran my hand over the driverside defrost vent and discovered that hot air from the passengerside defrost vent is partially mixing some with about a third of the driverside vent toward the center. The temp gradually decreases in the driverside vent from the center to the outer edge, where it measured 60*. In other words, in the defrost vents, the passengerside is uniformly 101*. In the driver side, the temp is about 90* at the right-hand side, which is the center of the dash. The temp in the driverside vent quickly decreases as you move away from the center of the dash. It appears that about 1/3 of the driverside vent, toward the center, is getting a partial mix from the passengerside hot air. The temp quickly decreases in the vent away from the center of the dash to where the left 2/3 (outer side) of the driver vent is about 60*. Whew! Hope that'* clear.

Placed the sensor back into the driverside dash vent toward the center, let it stabilize, 59*. Closed the passenger side dash vents and monitored the gauge. It peaked out at 61*. Guess that indicates that there may be a small amount of blending from the two sides, but it'* not enough to make the driver side 'feel' any warmer.

This morning the outside temp was 25*. In the driveway, the thermometer in the car read 24*. Cranked the car, let it warm up, and repeated all the tests while running around town. Had the same results, except for one thing. The high temp on the passenger side dash stabilized, maxxed out at 105*. The driver side eventually rose to 63*. The coolant temp gauge stayed the same as last night, at about 140*-150*. The defrost vents checked out the same, except for the slightly higher temp.

Just for my own peace of mind, I tested the airflow situation in a rather primitive way. But it did give somewhat of a visual confirmation of what my hands felt. I took a length of thin ribbon, maybe a foot long and 1/4 - 3/8 inch wide and tied it to the end of a long screwdriver. With the fan blowing at full blast, I held the ribbon in front of each dash vent and over each side of the defrost vent. There appeared to be some slight differences, as we previously discussed there would be, but all-in-all, the airflow seemed to be fairly uniform. If I had to swear to it, I would probably say that the driver side is likely a little less strong, but it'* hardly noticeable. There didn't seem to be any indication of blockage in any of the vents.

I don't have a clue how the temperature knowledge might help solve this issue, but it does confirm what those of us with the problem have been saying.

BTW, my white bonne is a stock '95 SE with manual HVAC.

Any thoughts?

Thanks for the diagrams, Bill. Do you know what years they cover? If they did put dual systems in the bonne, guess it must have been for awhile. Mine'* a '95 and Tim'* is a '98.

Jim

Jim.. by closing the passenger side since there are not two seperate controls in your car. There is only one batch of heat prepped for delivery. One delivery system aka fan and the biggest part of this that makes no sense is the air flow on the driver side.

If you have flow..you should (key word) have the same at the driver.

We need someone to disect a air box / vents etc to further find something that could cause this.

BTW Randman had one at his house last night and looked to find that what you guys are experiencing should not be possible.

Realizing it is happening, there is an answer and a fix.

The diagrams are from the '95 FSM that covers Bonneville, LeSabre, Park Ave, and 88 /98 Olds.

Just humor me, and check your RPO codes on the spare tire cover. You should find C61 for your manual system but no CJ2.

Assuming the system has no big leaks or holes in it, the only apparent source of cold air is on the evap side of the air mix valve. If so, the air mix valve must be leaking, misaligned, broken, unsealed, or otherwise faulty allowing cold air to bypass the heater core which somehow favors exit on the driver'* side. But we don't understand how this can happen.