I've noticed on very hot days (80-90F) that the effectiveness of the AC varies greatly withengine RPMs during the first 10-15min after startup. My Cayman S is equipped with auto climate control.


The example:


I get into my Cayman S mid-day after beingparked in the sun. I set the AC to lowest temp, recirc on, fan set to max. While driving, plenty of cool air emits from the vents. When I stop at a light, the temp of the air drops near to ambient in about 5 secs, then returning to cold once we start moving again. If I keep the RPM's up by maintaining pressure on the accelerator while stopped, the temp drop is not nearly as dramatic.


Has anyone else experienced the same problem? Most cars that I've had would experience a drop in AC temp at idle, but not to this degree.


I hate to take my Cayman back into the shop (it would be our first trip in after 8Kmi.) because I can't bear to part with it even for a day.

You can fix that by staying redlined...what's WRONG with you?? [img]/fckeditor/editor/images/smiley/MWPX/dance.gif[/img]


Paul

I am having the same problem you describe. The AC worked fine when new. I am trying to get a service call at Porsche. I will let you know what they say. My guess is that we have lost some gas from the cooling system. This fits the symptoms. Remmember this is strictly an educatedguess. My car has 2100 miles

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Having fun in Puerto Rico

They found some sort of condenser gasket missaligned. They fixed it and added refrigerant. The car cools fine now, even at low revs. It always cools a little better at higher revs, but it is acceptable now, even at idle.

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Having fun in Puerto Rico

Haven't noticedthe fluctuation in cooling you described, but the AC (manual) was only cool, not cold, esp on really hot days and runs over an hour.CS has only about 750 mi. Had Porsche service look at it last week: refrigerant low and small leaks found in both the evaporator and compressor--bummers. will have to take it in again when the new partsarrive.

It's more likely due to the greater airflow through the condenser when you aremoving versus when you are stopped. The condenser fan can only do so much with this heat. If itcan getdown to a cold temp when moving, I don't think refrigerant (or lack of it) is the problem. My car does the same thing in this stop-and-go Atlanta traffic.

Sheesh KaiserSozay,


That's discouraging! I hope my CS doesn't have the same problems because AC is really necessary here in Honolulu. Maybe Porsche service decided not to take a chance and will replace boththe evaporator and compressorwith new ones.

Hi KaiserSozay,


Thanks for the addtional info on your AC problems. It seems thatmost of the experiences of others with CSAC system in other threads are generally positive. My Porsche service manager just called to say that the new evaporator and compressor are in, so I scheduled the work for next Tue. It's supposed to take most of the day. I'll post the results after I get my CS back.