terryKS

Hi
Well I have got a A/C problem and Im looking for some advice:
A/C blows ice cold air as it should, then all of the sudden the air turns hot. When it does this I hear a (thump) come from under the dash, Im guessing this is a duct door of some type and its doing this as if im changing the temp control ****. My guess is a vacuum problem. It seems to do this when I let off the throttle(vacuum changes)? If I turn the a/c off for a few seconds, Im back in business with cold air. Any advice on where to start? I did do a search of the forums but could not find a problem of this type.
Thanks in advance!
Terry

crobtex

I've had them do the same when they were low on freon.

terryKS

well as a matter of fact I just had a new compressor installed today and they filled it up with freon. I was having this problem before the new compressor though. It seems to me that this must me a vacuum problem. The compressor stays running, it does not cycle off/on or anything. I know it had cold air to blow it just is not getting throught the proper ducts

tool

Letting off on the throttle will not increase your vacuum, this is not a gasser...........

terryKS

Oh!
I did not know that.

Tommy93w350

The diaphram module controlling the hot/cold vent must be leaking. I think it defaults to hot with out vaccum.

Quick fix, hook a wire (clothes hanger) to it and pull it open and tie it off to keep it cold.

premo 1

Where is the diaphram module you are referring to???