Good idea, will pinch off the hose going to the heater core as a test. I've converted other cars to 134a and had fine results. This one is strange.

I had poor performance from 134 despite all new components. I figured I'd try Enviro-Safe so I tried the industrial version.

Evacuated, flushed and pulled a vacuum. Followed the directions to the letter. No joy. Compressor engaged, low side pressure 25psi, no cool air, 95F ambient, 40% humidity. Added another 6oz can just for the hell of it, 45psi low side, no cool air coming out of vents. Heater is not part of the problem, I pinched it off to be sure.

I don't have high side pressures figures. Something blocked like the TXV?

You really need to post low and high pressures. Maybe something clogged the expansion valve.

I think that may be it. I went back to 134. I've got cold air coming out of the vents now but nowhere near as cold as it needs to be on a hot day.

I have an unrelated question: where did you get the Peugeot 505? where do you live?

Massachusetts. I found it on CL w/60k miles. It's a 1987 Liberte wagon and it's the 3rd Peugeot wagon I've owned. I love it.

All I did to the Peugeot is change the fittings to 134 and juice it up. That was three years ago. Blows cold. Can't understand how the W124 system is much different.