I know it is the wrong time of year, but with the heater questions (my
heater works great and gives hot air within one mile of home in 30 degree
weather) I have one related.
Does anyone with a 4k have a great A/C? Is it good? Fair? Mine doesn't
seeem to be up to the job. It can't keep four occupants cool on a ninety
degree day. It can keep the driver cool, but that's about it. The R12 is
OK, I had it checked.
Yeah, the A/C units pretty much match the heaters in terms of wimpiness,
One thing however to check -- if yours has an adjustable thermostat (as
in '83 UrQ/Coupe -- "temp" lever on bottom, about 1/3 "A/C" to the left,
"center" detent, then about 2/3 heat to the right, with above it two
levers for "footwell/air down" and "windshield/air up"), then the adjus-
table thermostat is itself adjustable (and thus quite capable of causing
much grief and aggravation...)!
The thermostat (not to be confused with the incredibly-annoying engine
temperature thermostat against which I so constantly rail!) is a small
rectangular box with the long copper capillary tube that runs into the
A/C evaporator/box assembly (sitting over the passenger's foot behind
the glove box in the UrQ/coupes, I suspect same for 4000s?). The thermo-
stat has a small 1/2-round shaft that engages the temp-control lever to
set the thermostat trip point (temperature regulation point). The whole
thermostat body itself "pivots" on the main housing -- this is the "ad-
justment" that calibrates the thermostat operation. The thermostat just
sits in a hole through which the 1/2 round shaft protrudes, and is held
in place by a little screw. You loosen that screw, rotate the entire
thermostat housing until it is operating in the proper temperature range
(nominally: 40-45F [or so] on max cool, medium fan speed), then tighten
down the screw, locking the thermostat body to the main vent/control
assembly. If that screw comes loose, then you might find that the temp
lever is just rotating the thermostat body/housing, and not actually
adjusting the thermostat itself...
On min cool (and, say, medium fan) the "cold" air should be sitting at
60F or thereabouts, on max cool the air temp should drop down to around
40F or so.
The downside to this 2-minute adjustment/check is that it will take you
two hours to disassemble the dash to get to the simple little screw...
As to reassembling the dash, well, have plenty of Valium handy, yeah,
Valium would be an excellant tool for working on Audi dashes (not to
single out Audi, they all suck, in my experience, with the possible ex-
ception of the Lotus Europa, coupla screws and the whole assembly is
sitting in your lap -- for better or worse...)
If max cool medium speed still can't get ya 45F air (in that nice balmy
70F November Phoenix weather), then your thermostat is probably dead.
(Mine failed in the opposite direction, locked full on, iced up the
evaporator solid! Brief 20F air [Brrr!!] and then nothing. Grrr!!! Boy
is it a, um, challenge to thread in the new capillary tube into the
evaporator; just keep trying...and when you least expect it [just as
you are ready to yank the #*$%^&@#*ing thing out], it will snick right
into place [and boy it is annoying when you manage to yank it out and
have to do it all over again!])
I doubt that it will ever truly handle Phoenix summers, but you might
as well get all of what little it does have!
You might also consider getting an aftermarket cooling fan to mount
directly to the A/C condensor to maximize the air flow; mine mounts the
condensor in front of the radiator and uses the radiator fan to cool it
off, almost as a side effect. When you're starting with 120F air, you
need lots'n'LOTS of airflow! One of the 10-11-12 inch units ("handles
4-cylinder engines") should do the trick.