I've had problems with my A/C, in particular, my compressor clutch doesn't engage. (2012 Ford Mustang, V6)
I replaced the low pressure switch and even bypassed the relay to ensure that the clutch is engaging (and it does engage when I bypass). Relay and fuses have also been checked.
I have a can of R-134A that comes with a coupler and a gauge. When I place the coupler (securely and tightly) onto the low-pressure line, I get no reading at all (both with the car off and with the car on, a/c running). If I press the trigger on the can, the pressure suddenly sky rockets to > 40 psi, and as I release, the needle drops to ~5 psi and gradually falls back to 0.
What could this be? Could I really have an incredibly massive leak? I don't see anything obvious in terms of leakage.