Hi, Back a couple years ago I had my R12 fitting replace with the 134a fitting. My coolant leaks if the car sits for a month or so, and so it did and it's time to recharge again. I have no clue where the recharge fitting is.

Can someone help me out?

thanks

Brian

under the plastic cover near the firewall on the pass side
you have to unscreww the low pressure switch to use the low side service port...
not sure about the high side though

So where did the shop change the fitting, on the low side or the high side?

b

You can add freon to the high side, its allot easier than digging down for the low pressure switch.

**BUT ONLY ADD FREON WHEN THE CAR IS OFF, NO COMPRESSOR RUNNING AND ENGINE OFF.**

I WILL SAY IT AGAIN ONLY ADD WHEN THE ENGINE AND COMPRESSOR ARE OFF, REMOVE THE CAN IF YOU START THE CAR, ELSE THE CAN WILL BLOW UP.

Get a pressure guage set the pressure to 60 PSI (both high and low side will be the same, when the engine and compressor are off). The 60 PSI is at an ambient temperature of 75 fahrenheit. Sometimes its helpful to warm the freon can in a bucket of warm water, it will fill faster.

NOW START THE CAR WITH YOUR HIGH PRESSURE GUAGE ATTACHED TO THE HIGH SIDE. (AND YOUR FREON CAN DISCONNECTED OF COURSE)

Turn the AC on full blast, and select recirculate, let the engine run 5 minutes your guage should correspond to the chart below. If pressure is too high, your over charged, if pressure is too low your under charged.

Follow this chart: (for correct charge)

Ambient temp(F) - high side pressure(psi)

65 f - 135-155 psi

70 f - 145-160 psi

75 f - 150-170 psi

80 f - 175-210 psi

85 f - 225-250 psi

90 f - 250-270 psi

95 f - 275-300 psi

100 f - 315-325 psi

105 f - 330-335 psi

110 f - 340-345 psi



Hope this helps
Rudy

cause of the switch attached to it..
you will need an adapter which comes in the conversion kits to charge the low side

As far as charging the high side I would not do that
the high side has atleast 100psi just sitting and goes up to 250-300 when the car is on
I don't think a can of freon can overcone the high pressure to get the freon into the system, unless you have a pump or something

The high side and the low side have EQUAL pressure when the car is off and the compressor is NOT running.

The only thing that creates pressure is the orifice tube (and the RUNNING compressor) take a pressure guage when the car is off (assuming your orifice tube is working) BOTH THE HIGH AND LOW have the same pressure. When the car is off, there is NO high or low side.

BY ALL MEANS DO NOT CONNECT THE CAN WHEN THE COMPRESSOR IS RUNNING. I DID NOT SAY THAT.

I said to add freon when the compressor and engine are OFF. You can add through the high side.

BUT YOU MUST NOT LEAVE THE CAN ATTCHED WITH THE COMPRESSOR RUNNING.

Like I said, ADD freon, DISCONNECT the can. Then check presssure(with A/C, engine on). If you need more freon SHUT the car off. Wait 5 minutes then connect the can again. And repeat, till you read the correct pressure.

RD

Ok.. this is weird. I went to get the A/C charged up. They had some difficulty finding the port, but they found it, it had a little blue cover on it.

When they went to charge it they started the car but the compressor wouldn't come on, so they said that they couldn't charge it. This doesn't sound right to me.

Are they smokin crack?

to do the 92 100, you need to unscrew the low pressure switch on the passenger side of car under the hood cowl as said above. then you need to jump the wires on that switch for the compressor to run while you charge it. and yes you need the adaptor that comes with the conversion kit to do this. you can buy the kit for $40, which comes with 3 cans of freon, gauges and adaptors and do it yourself in 20 minutes or less. just keep that adaptor for next time you need to charge it.... don't mess with the high side on this car.

So much easier to add on the high side, by removing the switch you inviting a new area for leaks and its pretty tight down screwing on the fitting etc etc...I belieive even bently says that freon should be added to the high side.

When the compressor is off there is no high side or low side. Its all one side

R

that only have a high side
and for removeing the switch it has a schrader valve just like your tire and the other A/C service ports so it wll not leak unleaa the valve is bad...besides that is the way it is supposed to be charged, by removing the switch...
all the A/C switches on the audi's are that way...

You might be right about them stating it for 96 and up. (but maybe they got smatter as they got older)

But once you charge via the high side you won' t do low the side again on these cars.

As far as the schrader valve I thought the switch had a o ring or gasket as well, which is usually not in the best condition on a ten yr old car. Beacause you do have to put the switch back in when your done charging. You don' t leave the adapter fitting with its new sealing power...

Its just a matter of preference I guess. I find adding freon (on the high side) then checking for correct pressure, easier that sitting there with 2 wires jumped and running the engine with a can of freon attached.

Just my preference I guess...but YES on most cars the norm is to charge the low side.


Rudy