Hi, Like I stated before, my unit cycles between 35 and 40 PSI suction pressure at idle. R134-a conversion. I blamed condensor performance on my less-than-desired air conditioning performance, but if that were the case it should improve noticably at speeds of 70 to 80 MPH, yet does not. I measured vent outlet temps Sunday evening: ambient 92F, interior cool, in shade: at idle, low blower, aux fan on high: 60 F outlet temp. Blower on high, outlet temp rises to 70F. Compressor and drier new last year, no detectible leaks.
Comments?

Is the fresh air flap closing all of the way?? Is it even closing part of the way?

With glove box liner removed, switch the controller between max a/c & then hit the EC button & watch that flap & it's 100% function between the two.

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I revamped all the vacuum pods several years ago. I also can hear the difference in blower sound when on Recirc. I will verify the flap operation. I know that when in recirc there is a little better performance. I also note that, when in econ, there is no apparent heating of the air, as would occurr if the heater core were flowing coolant, just air at ambient temp.
as a reference I put gauges on my 2006 GMC truck. At idle in high blower and recirc, 85 ambient, the suction pressure holds steady at 35 psi. Seems like 35 to 40 PSI suction on the 420 would cool a little better. Truck is very cold. As the Mazda people say, "Hummmmm...".