Pressure are low even for an ambient temperature of 50F. If your system is low, you have a leak. When you removed the caps to attach the gauges, was there pressure underneath the caps? The valves could be leaking.

Also when you use the bayonet fittings did you twist down the knurl knob to open up the valves?

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2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
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