Well the wife has started complaining about the A/C (Tinkerbell is a 2006 MCS) not keeping up with the Texas weather. Today when I was driving home it was 104F. So it's definitely hot here. Anyway her complaint is that sometimes it cools, sometimes not, when she in stop & go, it can get warm but start cooling at speed, but that's not an absolute rule.

So when she got home tonight, I immediately put on the guages to see what's going on. The high side was an incredible 260 PSI (at least I think that's incredibly high). As I let it run a couple minutes, it got up to 300. The low side is very low at only 10 PSI, which maintained constant. The fan is running fine.

So here's what my proposed diagnosis is. Partially plugged orifice tube. What do y'all think?

 

Since no one had a response, I'm going to post what happened. Perhaps it'll help someone else.

We took it to a mechanic - someone we knew years ago but found again recently. Anyway they found pressures as high as 375 with the low running about 50. So they evacuated the system, removed the condenser and cleaned it out. He did get some stuff out of it, so that could explain things. Pressure's are running at 275/30 which he says is pretty close to normal for our cars. He wants to run it a bit more and see if things change. He thinks (& I'm hoping) that the compressor didn't get damaged and should be fine for a while. At this point, the expansion valve might still need to be replaced (which is why he wants to run it some more). So it looks like slapping guages on it found a problem early.

 

TXV