I just checked the low side pressure on my Father in Law's 2004 Buick LeSabre (R134). It read 62PSI when reved and held at 2000 RPMs. The ambient temperature is approx. 105F here today. At idle he was about 10-15PSI higher than that. His A/C was recently charged by the dealership.

I just converted my w124 300d to 134a and I'm at around 40-45PSI at 2k RPMs.

Is this right for the ambient temp of 105F? Will it hurt to go higher (i.e. 62 PSI like my father in law's Buick)?

I noticed that my compressor clicks on and off pretty quickly if I go higher than 45PSI.

I'm not at all an A/C pro. I took the car to a shop to have the system pulled with a vacuum for 45 minutes before charging. I converted to 134a last year when changing the compressor.

Just looking for a few tips before we head out on an 8 hour trip. Cold air would be nice!

Last, has anyone compared Freeze 12 to plain old 134a?

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