I have a 1999 GMC Safari work van and juiced it up with a fresh can of 134a last night and decided to check the pressure in my 98 Expedition cause I had on 14oz. can left over. Well, the problem is I couldn't see the low pressure port. I saw the high pressure side right on the passenger side by the front right light and the accumulator/dryer looks like it is by the firewall on the passenger side but there is really no access to it, nevermind trying to put a gauge on it to check the pressure. Is the low pressure side on the dryer, or can anyone tell me where it is. I have a 5.4 XLT with rear air so I'm sure the system holds alot of freon and it feels like I should be getting a little colder than it is???Any help or suggestions is greatly appreciated!

 

The port you're looking for is indeed hidden on the bottom side of the accum./dryer you mention. Push hoses aside and feel around with your hand and you will eventually find it. Next, try getting a gauge on it....get the bandaids ready.

 

do I do this from above or below the truck?