Don’t Convert to R134a

AC will drive you nuts sometime, I’ve been chasing my tail on my Toyota, cools great when ambient temp is under 84, get to 94 and it runs then shuts off, turn off-on and it picks right back up for about 5-10 minutes then off again, never comes back on by itself. Tired of changing parts and loosing Freon evertine.
High pressure switch or high temp. As it gets hotter the refrigerant expands and system pressure goes up. Check your pressures when real hot. There are charts for temp and Lo/Hi pressures.