97 Riviera - replace Driver Air Mix Actuator

[edwinn]

1997 Riviera - 3.8 Liter, L36 - 141,347 miles


Earlier in the week the local dealer guys diagnosed the Climate Control issue as LEFT MIX DOOR ACTUATOR. They said a DTC was set, and I found in the G-Platform SM that Driver Mix Door code is: B1340, Air Mix Door #1 Out of Range.


Now I'm looking to replace the Driver Mix Door Actuator and found the part in stock at DelcoLine.




The dealer and another independent shop said labor would be 4.8 to 5.5 hours. The Service Manual procedure says to Remove the Inst Panel Carrier! WHAT?? Take the dashboard off?


The driver Closeout Panel is removed from under the dash, and I can see the actuators, and get a camera in there to take PHOTOS. Here is a pic of what I believe is the driver MODE (L) and AIR MIX (R) actuators. Will take better photos today, and try to exercise the CC to confirm the Act is faulty..




If you can get a camera in there and take a photo, then you can ALSO get a wrench on the two fasteners. Why does the IP need to be remove? a 5 hour procedure? This seems like a home garage job for sure.

Please comment!!


-Ed

[edwinn]

Was able to take some photos today after studying the Service Manuals. THREE driver side ACTUATORS cans be seen from under the DRIVER side dashboard with closeout panel removed.



Notice all three are the same part number.


Below the AIR MIX Actuator can plainly be seen at just the right camera angle, but it's not going to be easy getting in there. The Knee Bolster might have to come off.




It would be great to remove the Center Console for more visibility and work room, and I think one could remove the driver SEAT and lay back-down on the floor. The floor pan in and around the CTR CONSOLE area could be inspected with the console and seat out of there.


Here's one last pic of the AIR MIX Actuator, mounting screw, and the position of the valve shaft.




Do you think going in under the dash will work?


-Ed

[rkvons]

I went under the dash once on my Grand Prix for a similar issue. Basically, you can't see what you're working on while you're working on it. So you just close your eyes and reach up in there and let your imagination paint the picture you need. Be warned though, there are three screws holding each of those in.

[Tech II]

This is a dual system right? So there should be a mix actuator for the driver's side and the pass side......in the last pic, I see a bracket in front of the driver's actuator?.....in others, I don't see the bracket...was it removed?

It's just two 5.5 MM screws......

If the bracket is in the way, and the bolts holding it in place are buried, I would seriously think of cutting it out. Or if there is enough of a gap between the bracket and actuator, drill a hole in bracket so you can get to the other screw....

Sure the time they were quoting was for the actuator or the temp door itself?

[brcidd]

I've actually broken the tab off the hidden screws before- and let just one screw hold it in place on replacement actuator- what the heck, it works and saves pulling the dash and HVAC module...

[Tech II]

There is always "ANOTHER" way to do a job......flat rate guys are the most "creative".....

[rkvons]

I say 3....

[edwinn]

Originally Posted by Tech II

This is a dual system right? So there should be a mix actuator for the driver's side and the pass side......in the last pic, I see a bracket in front of the driver's actuator?.....in others, I don't see the bracket...was it removed?

It's just two 5.5 MM screws......If the bracket is in the way, and the bolts holding it in place are buried, I would seriously think of cutting it out. Or if there is enough of a gap between the bracket and actuator, drill a hole in bracket so you can get to the other screw....

Sure the time they were quoting was for the actuator or the temp door itself?

1997 Riviera - 3.8 Liter, L36 - 141,627 miles

Sorry for not replying earlier. I was getting NO thread notifications. Yes it's a dual system with separate Pax Temp control. The bracket you describe hasn't been removed.. just a more direct camera angle. Probably won't be much trouble getting to the screws. I have all kinds of right-angle, u-joint tools/bit/sockets and LOTS or 1/4" drive stuff.

Several shops are quoting "from the book" around 5 to 5-1/2 hrs plus part marked-up 2x. I think the challenge going in there from underneath isn't reaching the screws.. it's getting to it IN GENERAL. Might be possible to remove the driver seat and then lay on your back 'on floor' to change the actuator.

-Ed

[edwinn]

Originally Posted by brcidd

I've actually broken the tab off the hidden screws before- and let just one screw hold it in place on replacement actuator- what the heck, it works and saves pulling the dash and HVAC module...

Yep.. agree totally. Don't really want to pull the dashboard. Something will get cut, scraped or damaged.. and possible another problem will arise due to major disassy/assy. Plus it will cost 800 bucks or more. Still think if I remove the driver seat and lay on [my] back, the actuator can be reached. Plus I have a LOT of small electronic and 1/4" drive mechanic tools to reach up in there.

The problem is a COLD weather one. In summer, cold air blows from all registers. But in winter.. there is Hot air coming from Drv side, and Cold air coming from Pax side. It's not making sense. Do those symptoms sound like a stuck DRIVER MIX DOOR to you?

I'm not convinced that's the problem and would like to observed actuator shaft index/tic marks, either electronically of visually, on both Drv and Pax units while ranging hot-to-cold first. What about calibration and setting (or initialization) of the door position?

-Ed