Re: audi 5000 a/c

[zm@mhcnet.att.com]

> 1. Bentley sez "don't top it up. evacuate all freon and replace."  Is this
> 
	I noticed this in the manual too and was wondering why. There is
no explanation given. The A/C compressor in my car (87 5000 CSTQ) is made
by Nippondenso which probably makes most A/C systems for Japanese cars.
Nowhere have I heard that a system evacuation is needed for low freon
pressure. Its only when the system is opened for repairs and air gets in
is a evacuation called for. I would just add more freon to get it within
spec.

I might have to do the same on my car since I find that the compressor
does not seem to cycle on/off periodically like its supposed to. So I'm
wondering if its low on freon - it cools fine though. Also, on my car, the
A/C creates a considerable drag on the engine during acceleration until
the turbo boost picks up. Is this normal? It seems to be excessive
compared to other cars I've driven. I'm wondering if some of the compressor
oil has leaked out and needs replenishment. Any ideas?

> 2. Bentley shows only a high pressure port.  How does a weekend mechanic add
> more freon?  Is there a low pressure port hidden somewhere, or is a $2500 
> machine required to add more gas?
> 

When I was under the car staring at the compressor clutch, I noticed a 
port right by (or on) the compressor. You'll have to look from under the
car to see it. I presume this is the low pressure port. Make sure with
a pressure gauge before you hook up the freon - the pressure is high enough
when the compressor is running to burst the freon can.

Hope this helps. Let us know how you make out.

Zafer