Hi. Why does the AC in my 940 and 960 fade away and hot air blows when I accelerate? The cool air returns when my acceleration levels off. Don't remember my old 240 ever doing this.

Bad Vacuum Bellows on these cars (bad design).

You can put a golf tee into the line for the bad double acting bellows on the drivers side. It's a stop gap measure but it works and keeps the air flowing thru the dash vents. I think it's the yellow (or red) vacuum line from the electronic manifold.

DEWFPO
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1998 S90 071,245 and 1995 964 154,100

DEWFPRO,

Can you be a little more specific on where and how to place the golf tee? I have the same problem and am not terribly mechanical but I bet I can do this if explained properly.

On the drivers side. Take off the under dash cover (a few of screws on the dash, and few snaps on the center console and it's off). You will then see the 3 vacuum servos (bellows) in front of you. Only 1 of those 3 will have 2 vacuum lines coming off of it. IIRC it's the on closest one to you and you will be looking at it from the side.

One line is BLUE (defrost side) and one is YELLOW (floor side). I pulled off the Yellow vacuum line and plugged it with a golf tee. Then I took the car for a drive and dash vents functioned properly all the time (no dropping out on accelleration).

Then just snap the cover back into place and put the srews in and your off.

It's not a fix, just an end-around to keep the dash vents working in the summertime.

Note : By doing this, you will have no heat coming out of the floor vents in the winter (it will be coming out of the dash, etc..) so the solution is to replace the vacuum servo.

I hope this helps.

DEWFPO

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1998 S90 071,245 and 1995 964 154,100

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