Problem remains. Did this tonight; 1. Removed valve cores and checked for leaks - all ok. 2. Verified in and outflow through each valve core (hi/lo sides) both with and without manifold set - all ok. 3. Blew compressed air through high and low sides - and verified I have flow in the circuit - Air co...

I'm starting off with a new Freon tank, so that is not the issue. I'll look into the gauges/fittings being the issue and will report back what I find. When pulling a vacuum it took ~5 minutes to get to 29mmhg. Is it possible the manifold set or the schrader valves work on vacuum but obstruct inflow?...

I'm fairly experienced doing ac work, but I'm stuck in a rut. Vehicle in question is a 2007 Toyota Sienna. It uses a variable displacement compressor with a magnetic clutch. There are two evaporators - one up front and another in the rear of the van. System Freon capacity is 27.5oz of R134a. To unde...