I have a robinair cooltech 34700z machine. When I hook the hoses up to the car I can see the small bubbles going in to the oil injector bottle, the machine works fine but it will sit forever on recovery mode and will not drain oil. Are this two problems related? and what is the problem?

Measuring Tools & Sensors - Robinair - Cool Tech 34700Z Recovery, Recycling, Recharging