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So I haven't had good a/c for a while and after a trip this past week I decided to check it out. Blower Motor works at all speeds but I removed it anyway just to see if anything was clogging the passageways. I did find a small bit of mouse house in the areas that I could reach and even got a bit of vacuum cleaner hose into wherever I could. The compressor turns on when a/c is selected, the air changes to hot on both driver and passenger sides when the temp selection is moved to a high temp, but I don't hear a big difference when I switch from outside air to recirculate, which seems odd in comparison to what I've experienced in other vettes. When I went to clean the udders, I noticed a bunch of mouse evidence on the drivers side rearmost udder and at the rearmost of the wiper box. All of this leads me to think that there may be a clogged condition somewhere in the a/c system. Soooo, what do I do next??? Is there any way to clean the evaporator and make sure that the airflow is not obstructed? I would appreciate any help/suggestions as to where to start first, then steps to take next until I get the system working correctly. It's a vert, so we haven't been terribly inconvenienced without a/c but these hotter summers have made it less enjoyable to take the car out. Help please.
Do the air paths change when you select different modes? As you have noted, the volume of air movement should change considerably between fresh and recirculate. Leads me to wonder if you have a good vacuum to the control valve.
I have yet to hear of any reasonable access to the evaporator, even just for cleaning the outside of it.
Air direction is controlled with vacuum signals, and air temperatures controlled by electric actuators. If the a/c light stays illuminated with the system on, then you should have at least a modicum of refrigerant — though not necessarily enough. Air modes are less important than cooling — misdirected cool air will still cool the cabin. Been there.
If you have access to gauges, or even a service can with a gauge, you can verify the approximate refrigerant level. With the engine off and static for several hours, the high and low sides will equalize and should have a pressure very close to ambient temperature, i.e. 90 psi on a 90 degree (f) day.
I had this exact same problem about 8 months ago. Air flow and temps changed with the controller but regardless what mode I was in, the air came out of all the vents at the same time. This caused a very weak air flow. I took a cfm meter and at the dash vents I had 125CFM. The blend doors are vacuum controlled and electrically operated. I had a leak in one of the vacuum lines behind the passengers side wheel well. Once that was fixed, the CFM was 523 if I remember and you could hear the doors operating.
Last edited by yellow2007; Jul 23, 2024 at 07:50 AM.
You could also try to recalibrate the doors:
Ignition off
pull fuses 18 & 27 from passenger footwell
turn ignition on (no start)
Wait around 5-10 minutes
turn ignition off
replace fuses.
Thanks for the tips. guys. I will try to check out all the suggestions. Wife and I are going to display the car at the Pittsburgh Vintage Grand Prix next week and I was hoping to have some a/c beforehand.
Thanks for the tips. guys. I will try to check out all the suggestions. Wife and I are going to display the car at the Pittsburgh Vintage Grand Prix next week and I was hoping to have some a/c beforehand.
If you have access to a smoke machine, that'll help determine if it's a leak or not.
Air Conditioning not working
