FAQ: Warm/Hot Air on Drivers Side, Cold on Passenger Side

It's probably one of the blend door actuator motors for the hot/cold issues. It would be solder/bulb related for the dim lights. Two separate issues.

Welcome to the board!

Thank you - Where are these door actuators located and how difficult is it to get to them?

If it is the actuators, are 95-96 actuators compatible with 97's? There are several 95-96's in my local yard that I could get parts from. The control panel is different, though... Thanks again.
Mikel

https://rivperformance.editboard.com/interior-f20/write-up-hvac-assembly-t2500.htm#27279
Mikel, the above link is in the "Write Up" section on this board.
These are what you are looking for and are very easy to find and access.
Just need to see which one isn't working, all they do is turn the blend doors open or closed. They are small electric motors.
Some are on the passenger side and a couple on the drivers side.
Based on your problem the one you are looking for is on the passenger side.
Remove glove box and look to the center on the instrument panel you can't miss them.
Try operating the HVAC controls while you are watching and listening for these to operate and you'll find the one that doesn't work.
I believe that the earlier cars had the same P/N's, but you can easily see the P/N' marked on the units themselves.

Mikel wrote:

Thank you - Where are these door actuators located and how difficult is it to get to them?

If it is the actuators, are 95-96 actuators compatible with 97's? There are several 95-96's in my local yard that I could get parts from. The control panel is different, though... Thanks again.
Mikel

The three on the drivers’ side are accessible by removing the sound insulator, the two on the right are, as Rickw said, behind the glove compartment.
They are the same number, or will work anyway for all years. The one I was missing out of one of my '99's I replaced with one from my '95 parts car.

Also, if you go the junk yard and they are cheap enough you might as well get a spare.

Hello,
Quick update:
I opened up the passenger side and replaced the left hand side servo (mixer door) with a junkyard one. It now seems to go from scolding hot to freezing cold!

The other problem I have is that the driver's side temperatures are a bit erratic, typically from a bit warmer to much warmer. I pulled the lower driver's side panel and ran the heat settings through the entire range. The lowest servo moved, but did so in a jerky manner. I moved it to the coolest setting and uplugged it. I'll replace it with another junkyard unit next week. Good thing my local yard has five 95-96 Rivieras! The servos in the driver's side don't look easy at all to access from underneath.

Speaking of problematic climate control systems, I wish the Confortron in my '66 Toronado was so easy to work on!

Thank you all.
Mikel

Another item to check: Be sure that flex hose that connects to the drivers side knee bolster, on the upper right hand corner of the bolster, is connected, it is the temp. sensor for the passenger compartment and if it isn't connected the system will not get proper readings.

Mikel wrote:

Hello,
Quick update:
I opened up the passenger side and replaced the left hand side servo (mixer door) with a junkyard one. It now seems to go from scolding hot to freezing cold!

The other problem I have is that the driver's side temperatures are a bit erratic, typically from a bit warmer to much warmer. I pulled the lower driver's side panel and ran the heat settings through the entire range. The lowest servo moved, but did so in a jerky manner. I moved it to the coolest setting and uplugged it. I'll replace it with another junkyard unit next week. Good thing my local yard has five 95-96 Rivieras! The servos in the driver's side don't look easy at all to access from underneath.

Speaking of problematic climate control systems, I wish the Confortron in my '66 Toronado was so easy to work on!

Thank you all.
Mikel

Greetings!

Where are the pics of the Toronado?

Bert

ibmoses wrote:

Where are the pics of the Toronado?

Bert

Since you insist...

Very nice car!!! Looks restored.
How does it run and drive - as good as it looks?

Rickw wrote:

Very nice car!!! Looks restored.
How does it run and drive - as good as it looks?

It's a nice unrestored car that I bought in Colorado and brought to CT, never to be driven during the winter except in and out of the garage. The paint is not holding up very well and the chrome is slowly deteriorating. But from 30 ft it looks beautiful. I just rebuilt the TH425 and put a very low miles 425. The confortron is beyond hope. I'll have to go over the maze of dry-cracked vacuum lines some day...

https://s305.photobucket.com/albums/nn223/bw1339/My%20Toronado/

I love those old cars. That looks like something Dean Martin would cruise.
There is a 68 Toronado down the road from me in very good condition. The lady that inherited it is fool and pulled it outside about six months ago and is letting it ruin. Before that it was garaged since new. It wont take long for the sun to ruin the interior and all the rubber components on it.
She said the "insurance man" offered her $10,000.00 for it a few years ago...it will sit there and ruin.

Bert

Make her a low ball offer of about a thousand. Promise her you'll take very good care of it, etc, etc. You never know what could happen.
The worst thing she can say is no, at this point in time. Then somewhere in the future she will think about it and let you have it.

Mikel wrote:

The confortron is beyond hope. I'll have to go over the maze of dry-cracked vacuum lines some day...

Here is a website that might help with that:

http://www.toronado.org/

One of the Technical Advisors from the Riviera Owners Association started the Toronado Owners Association; I think it's a very informative site.

99Rivman wrote:

Mikel wrote:

The confortron is beyond hope. I'll have to go over the maze of dry-cracked vacuum lines some day...

Here is a website that might help with that:

http://www.toronado.org/

One of the Technical Advisors from the Riviera Owners Association started the Toronado Owners Association; I think it's a very informative site.

Thank you. I've been a member of the Toro list for years... There is a lot of cross-pollination between the Toronado and Riviera worlds

It's more a matter of finding the time to tackle that job...

Mikel wrote:

Thank you. I've been a member of the Toro list for years... There is a lot of cross-pollination between the Toronado and Riviera worlds

That's true, to give the TOA a start, they were invited to join this years ROA International Meet. There were six Toronados out of 66 cars; I guess it was a start anyway.

I know this is an old post, but I had to bring it back because IT IS RELEVANT information that I'm about to post. I also see the topic got off track a little, but whatever - no problem!

So I had this same hot side/cold side problem in my Riviera that I just discovered this morning. I followed writeups and whatnot and found the servo motor assembly that turns the directional air vane inside the dash tubing. I took it out, disassembled it, it was perfect, so I put it back together. I got back to the car and loosened up the shaft that was attached to the air vane. Fine - good. All seems well. Well, I still had the problem when I turned the AC/heat on. After some tinkering, I found out that the servo gears them selves were MISALIGNED!! Go figure!

Now for some facts and other information. The servo itself turns the gears inside and the air vane only over a CERTAIN range. This range is marked by two lines on the cover of the servo, the right side being the cold direction, the left side being the hot direction. Whenever I'd plug my servo in, it would go WAY too far to the cold side, so that when i turn the temperature all the way to hot, the misaligned gears were still only turning the servo and air vane to a still-cold position. I kept realigning the shaft gear until when I plugged it in and started the AC/heat, it started in the coldest postition (60F), which was also the correct position for the air vane.

It's very confusing to explain, but I found it to be very useful information and a possibility when exploring this problem, even if it's with a different servo. If anyone didn't find this clear, PLEASE ask me questions! It is very complicated to explain.

Thanks!

-Z

You had to index the servo to match the position of what your referring to as the air vane shaft.
Correct.?

In my car, the driver's side is ALWAYS warmer than the passenger side. The servos all work fine (I replaced two with broken gears in the past). I was thinking of indexing the gear with the encoder one or two teeth in the driver's side servo to offset this.

Correct Rick. From what I found when I was messing with it last night, the servo motor itself is told my the HVAC controls to move only a certain distance. The main drive gear for the air vane was out of alignment and wasn't moving to the correct positions so I had to keep taking it out and moving the drive gear until it was positioned, by the computer's temperature setting, in the same direction as the air vane. I wish I would have gotten pictures...

Mikel - that seems to be what I just did last night, so it's worth a shot! I don't know exactly which servo needs attention, but that sounds like the issue. It sounds like it's one on the driver's side inside the dash.

Exactly which servo did you remove that controlled driver/pass temp? i've pulled a few of them, but i seem to pick the wrong one always

The one I dealt with was behind the glove box and immediately to the left and behind the PCM. It was the only one I could see on my '95. I unscrewed it with three 5.5 mm screws, one electrical plug, and then popped it off the air vane shaft. After you remove the PCM, it's easy to get to and take out, as I described.

Please note, though, that the one I messed with is not the only one that controls temperature blending, but it was the one that was causing my problem. My driver's side temperature would always adjust as it was supposed to, but no matter what, the passenger side would always be cold. Therefore, the passenger side servo/air vane was the problem.

ah, i see. my problem is one of the driver side blender doors, but i am trying to find out which one. Neutral driver side and cold on the passenger side. everything else works fine.

Mr.Riviera wrote:

ah, i see. my problem is one of the driver side blender doors, but i am trying to find out which one. Neutral driver side and cold on the passenger side. everything else works fine.

As much of a pain my Riviera's HVAC system is, it always amazes me how simple and easy to service it looks compared to my '66 Toronado's Confortron automatic system, with its miles of vacuum hoses.

By the way, I'm a firm believer that the last generation Riviera was exactly the car Oldsmobile should have built as a successor of the Toronado.

Mr. Riviera - sounds like you might have a combination of them not working correctly, though I can say for sure that if the servo/air vane is the problem, at LEAST the one I worked on is the same one that youre having an issue with.

Mikel - I cannot imagine tangling with that many vacuum hoses lol. The system for just my '88 Lesabre T-type is crazy enough and it's nothing like a '66 ANYTHING.