I am new to this site and looking for some help. I live in South Louisiana. I am having some odd problems with a vehicle I purchased about 2 months ago. When I got it, it would take a couple minutes to start cooling, then it would cool down to around 40 deg F inside (in 70 deg weather) then stop cooling for a couple minutes until it got to about 65 deg F inside then it would start cooling again until around 40 deg F and so on and so on. I had added a 12 oz can of coolant and it improve slightly for a couple days and then went back to what it was doing before. This past weekend I went meet a friend out of town who had a vacuum pump and drained the system completely and held a vacuum on it for and hour or so. It pulled 30 in vacuum and after an hour or two it dropped to 25 in vacuum. I then refilled the system with synthetic "artic freeze" R134a coolant. I have dual AC units and it called for 3 lbs 8 oz freon which works out to 56oz. We put in about 54 oz and it seemed to be cooling decent. It got down to around 50 deg F after idiling for 10 minutes or so in the driveway. The high side got up to around 200 in the 80 degree weather and the low side was around 40. I turned the vehicle off for a couple hours and then got back in it later to head home. It started the same senario all the way home cooling down then warming up, cooling down the warming up. I went to the store to get a can of freon to top it off (since it was technically still low) and immediately after pumping some freon in, the clutch engaged and it began cooling well and did the way home for 5 minutes or so. I thought I had cured it until last night when I went to class and it didn't cool until after 5 minutes or so. I just changed the AC relay in case that was bad but its still doing the same thing. I did not change any parts while I had the system empty which was probably a mistake looking back now. Can anyone please provide feedback on what I should do next?