Recently purchased a 91 SL300, and sorting through a few issues.
The only major one seems to be the A/C.
Worked "okay" when I drove it 200 miles home last weekend, but gradually getting less and less cool this week (it's 98 degrees this week, so I'm asking a LOT of it, granted) :-(

Figured I'd check the freon pressures (it's already been converted to R134a), and all I can get the gauges to read is about 105psi on both the low and high sides with the a/c on.
Any possible reasons or things to check for why I'd have no differential in comparing low and high-side pressures??
Thanks,

__________________
Barry