[czm400r]

I have just added 2 cans (12oz. of 134A and 2oz oil each) of quick cool to my AC system. The air is very cold from the vents but the Comp. clutch does not stay engaged very long before it turns off and then back on. Am I still low on Refrigerant or is this the sign of something bigger.

UPDATE, I have driven it around with the air on high. Popped the hood and the compressor is runing full time. Now to check the level or pressure. the Auto parts store sold me a guage (Like a Tire guage) but I can't seem to get it to work, Is there a better way to check the level.