This thread on 124 series ACC repairs is very useful.

With some great advice from George Murphy of Performance Analysis, I've gotten far enough into diagnosing my own ACC system on a 124 series 1988 300TE to determine that the defroster actuator #38, the center nozzle flap # 40 and the two for fresh/recirculated air #42 are all leaking.

I have a couple of questions on this topic.

Anybody have any experience with ACC Actuator repair kits from Autolux? www.autoluxmbz.com

I'm concerned that their kits may result in the same limited motion Dave describes as a drawback to the actuator rebuild diaghragm kits sold by Performance Analysis.

Here's where I need some strategic advice from you folks who have been down this road. This car has 193Kmi and needs plenty of other work, my budget is tight and my time limited. I'm looking to get two more years out of it for daughter #2 to drive to college.

If I replace only the easy one - the defroster actuator #38 can be reached through the glove box opening, will I get any improvement in operation?

How do the various circuits default with no vacuum?

I never bother with the recirculator switch, so that's not really essential unless as I suspect, the ACC unit uses it to optimize speedy cool down or warm up depending on outside temp. Similarly, we can probably live with cold air coming out the side vents only and skip replacing the center vent actuator #40.

If I go this route, should I cap the now abandoned circuits at the vacuum block?

Thanks for any and all advice.

Jerry Murphy

'88 300TE
'97 E420
'97 Audi A6Q wagon
'67 Morgan +4
'37 Cadillac 7553 V8 Fleetwood Town Car