Hello forum, new(ish) 240 owner. My family has owned and driven several 240s and 960s over my life. This one kind of fell into my lap from some family friends. One of those "if you ever sell it let me know" type deals. Anyway. White 240 auto, the car was converted over to 134a in 95 according to the sticker. I had some left over 134 from something else I was working on, and I put in just enough to see if it would hold it and pressurize the system and short cycle the compressor. I then drove it on the few days I didn't drive my suburban to work during the winter, and it held the little bit of pressure I had in it. So I filled it up about a week ago with a bottle from auto parts store. The compressor cycles fine, and it blows fantasticly cold at idle, but if I drive anywhere it blows like the heat is on. Then at a stop light, blows cold again. I was wondering of the 240s had a vacuum operated blend door and I'm losing vacuum or what? Thanks in advance for any insight you guys can share.

 

There is no vacuum operated blend door on a 240. I'm not familiar with the operation of the air conditioning systems on the 240 as I have long since removed most of the AC components from mine due to an accident. Perhaps others can chime in. Maybe it's overfilled?

 

the air flaps on the 240 are vacuum actuated, but the heater valve is cable controlled, there shouldn't be any heat if its off. the recirc flap might be opening/closing?