I have a 1999 Dodge Caravan 3.0L with a single A/C.
I need to add r134a due to over a few months the A/C air is still cold but not very cold.
My question is where can I find the low pressure port ?
Can you give me a location and what to look for ?
Many thanks
A J

 

it is on the left side of the radiator, under the water hose, between the radiator and engine!

Check

 

So far I can only find a connector port with a black plastic cap, which is located, looking from the front of the car, is situated on the left hand side about 15" before the a/c pipes meet the firewall going towards to the interior of thecar.Is this the low pressure port ?

 

no! that is the high pressure! the low is near the radiator under the big water hose ! you have to move the hose to see the valve.

between the engine and radiator on left side

 

Thank you very much for your help, caravan99, I will be checking when I get home at the end of the day, and tomorrow will add a comment.

 

Yes, I have recharged with a 18oz. can and took almost all to get to 35 psi while vanwas idling and when reving it to about 2500 to 3000rpm's the psi drops to about 20 psi. I noticed that when I disconnected the can from the low pressure port, I could feel thatair is coming out when idling, but when I put the plastic cap back on the port, I did not noticed any air going out. Is this normal ?

 

I guess you know that you need the engine idling and the A/C on max. If the pressure is to low, the A/C compressor will be off and when you fill with gas 134a the compressor will start to run alternate (on - off) for a little time till the preassure is higher - ( When the compressor is off the pressure go high and when the compressor go on, the pressure will be lower). you have to fill it till the compressor don't stop running. BUT becareful tonot pass the maximun pressure.(check on the gauge).

IF GAS IS GOING OUT FROM PORT, -- IT IS LEAKING!!!