To: BS911 - enjoyed your article on 993 AC system. I also read article at http://www.bergvillfx.com/porschehvac2
I am trying to diagnose a problem on my 1996 C4. Clutch not engaging.
Question: do you know if the low pressure switch is normally open, or closed at proper pressure?
If 'closed' is normal, I should read 0 ohm across pin 4 (Black) and pin 1 (white/orange). And if I read an open circuit, will it be save to jump pins 1 and 4 on the plug, to try and engage the clutch? Or is there an easier way to jump the clutch back in the engine compartment so I can get the compressor running and see what my AC gauges say? thanks, Bick51, Aiken SC

I do have a problem w my 97 A/c can we communicate on it? thanks david d schiff @ man.org or 707-7044948 mobile

Hej -saw you great piece on ac issues-I did not see my issue My 1995 c2-everything works fine but after a bit you can smell a bit of electrical smell. I remember something -servo perhaps in the footwell of the passenger side. I could us some help as no one seems to respond to this. How to fix would be great and or part and #. you can always email me -gg@gallerygimbel.com
Cheers Sam

Brian,
Read your great write up on the 993 A/C system WOW! using it on a problem i have!

I have a '95 993. I only get 50+ F air mid vent at 85F o/s. The pressure is 15L and 250H at 2K for ten mins which is right!

All other system aspects are in order. leaks etc.

The comp cycles on and off every 30 sec once it reaches its best 50F. The tech who serviced the system jumped the comp to be constantly on and it got down to 44F with in 2 min.

What could cause the comp to cycle so often? The tech suggested that the sensor at the evap might be bad. Is this a possibility? You mention this sensor and how to check it looks easy but is this sensor a likely culprit? Could the actual CCU internals be bad?

I am sure the cycling is at the root of my problem please any and all ideas are welcome.


TX in advs for your help and insite!
Paul Teske
ABQ NM