2007 Kia Optima A/C issue
I have a 2007 Kia Optima, and it ran low on a/c "freon". I replenished it, it builds pressure like normal on low (30) and high side (175), the clutch engaged and the compressor running, then it tries work, the high-side pressure drops to (100 psi) level and a/c doesn't blow cool nor will the high pressure go back up until I shut the car off, restart the engine the process repeats itself. This happened each time the car is shut-off then restarted.
Sounds like the orifice tube filter is clogged or the expansion valve is not working depending on which one your vehicles A.C system has.