[hill8570]

I've got a 2002 Sequoia with the dual A/C. The A/C has never cooled all that well since I bought it (back in 2005), but since it was my first R134a A/C, I figured it was just the refrigerant. I did a bit of adjustment on the water control value based on some TSB for that model, but it didn't seem to make any difference. I also checked to see if the TSB for the compressor had been applied, and it looks like it had. However, while fixing the A/C in my wife's 1995 Camry (which I thought was R12, but turned out to be R134a when I checked the specs), I realized that it's possible for an R134a system to be colder than a witche's t*t when adjusted correctly.

So, I'm now trying to troubleshoot my rig. Symptoms are: somewhat cold air when it's not too hot out, colder at highway speeds. Occasionally gives up the ghost entirely and just blows hot air (usually on the days I need it the most).

I've checked the auxillary pusher fan in front of the condenser, and it seems to be working OK. The condenser itself seems clean. When the system is running, the sight glass is milky white (not just bubbly), but is clear when the system isn't running. Operational low side pressure is 53psi, operational high side pressure is 245psi. Ambient around 85-90F. According to the FSM, specs for the dual A/C are 36-51 psi low, 275-305 psi high, so my high side pressure is pretty low, and the low side pressure is pretty high.

To me, the pressure readings sorta-kinda indicate a duff compressor, but I don't understand why the sight glass is milky white. Any suggestions?