I have a 1995 Volvo 850. The compressor is cycling on/off every 5 seconds. I bought a cool air kit from Walmart for 25 dollars US. It includes a blue rubber hose, pressure gauge, a can of r134a and a valve attachment to screw in to the top of can.

My questions are:

1. Is there a high pressure point and a low pressure point. I know that one has to recharge using the low pressure point and where would that be located? If there is a high pressure point also, where would that be located also. Are there any web sites which show pictures or diagrams of the low pressure point of an 850 air conditioning unit?

2. Is screwing the head attachment on to the top of the can with a clockwise motion enough to break the seal and release the r134a freon. Or does one also have to use the valve in a clockwise motion to break the seal and then use a counterclockwise motion to release the refrigerant. If this is not correct, could someone guide me through the steps.

Thanks. Charles