There are no leaks. Hmmm - "famous last words". 175 is low for high side pressure measured at 1800 rpm, you should next have the refrigerant pulled out and weighed, I suspect a leak. Leaks can even occur from bad service valve caps. Its a JX.... I borrowed my friends recovery machine and ...

Unless you dealt with R4's when they were common in daily drivers 15+ years ago you don't appreciate what a headache they were. My only experience with R4 compressors was on my own '88 and '94 Suburbans, which were orifice tube in front and expansion valve in the rear. The 1988 was R-12, the 1994 f...

As for weigh of the Freon. I use 12 oz cans. is that 12 oz by weight or volume? Should I use a scale instead ? Eric OK, sounds like leaks in both condenser and evaporator. I use cans as well, as I'm not "a professional" and do pretty much just my own vehicles. R134a can be added by cans, ...

I'm in Arizona, Phoenix and Prescott, so it's hot here - 108F in the shade today in Phoenix (as if there's really any shade !!!). That said, the local radio show ASE mechanic says that vent temperatures need to be 55F or less. That said: my vehicles do better than that, measured with digital thermom...

7echo wrote:Evaporator is under the dash, '93 Chevy truck.

I was thinking there may not be an expansion valve?

Likely an orifice tube in the engine compartment, no expansion valve.

7echo wrote: Is there a way to properly flush the evaporator?

Whatcha got? For sure any expansion valve would need to be removed first.

I will be working on this car again within a week or so, I will post back. Maybe it will be sooner because its my daughter's car and we live in Phoenix where the temp is above 100 almost consistently...LOL Yep, I'm longtime Phoenix resident, now split time with cooler Prescott area....pretty unbear...

When the engine/compressor is running, the low goes to about 35 and the high to about 175 and stays there constantly. The compressor never turns off. What rpm are those pressures measured? Should be like 1800 rpm. There are no leaks. Hmmm - "famous last words". 175 is low for high side pr...

I've used Smart Automotive in north Phoenix for over a decade, for any stuff I haven't been able to do myself (I do well over 90% of my own maintenance and repair). They are honest and reliable.

I used the Autozone loaner R134a service gauge kit and electric vacuum pump up near Prescott, when most my own stuff was down in Phoenix. I felt both were pretty good units. I used my own can tap though, so not sure why you had an issue with the kit's line. Currently my PSI readings are 34/340 (low/...