So my first instinct tells me its the A/C system that is leaking the green fluid. I noticed a small green puddle under the Cat area.

I recently attempted to recharge the A/C due to its sub-par cold air. After that the A/C compressor has been making a louder noise when on, and kicks on and off very frequently. I would say more than normal or maybe I just notice it more because I can here it clicking on and making a weird noise while on. I also noticed a few weeks ago that the purging sound came from the front end. Sounded like a turbo BOV (I do not have). I was just able to duplicate the the noise by turning the A/C on and revving the engine. Not only did I hear the purge but I saw a vapor like cloud come from, what looked to be like, the turbo area. That's when I noticed the small very bright green puddle under the turbo area on the ground.

I've had a suspicion lately that the compressor is going bad with the loudness and lack of super cold air.

Basically I'm looking to see what yall think or if you've heard of this before. I've very curious of the purging sound.

The compressor a DIY job? Or what would I expect an indy shop to charge for it...

 

Under the cat? Are you sure you don't have a coolant leak?

 

The A/C systems leaks as a gas. There is no fluid. It's coolant.

 

There is oil in an A/C system. It may, in fact, be green. If the system is overcharged, there is a valve that will purge excess pressure in order to avoid blowing a hole in the evaporator or a high-pressure hose. Not sure where this release valve is on a MINI, though, sorry. If your coolant is still at the proper level, a stop into an A/C shop may be in order, at least for diagnosis.

 

All Mini's have sub-par AC's as well as cheap AC compressors, especially in this scorching hot weather. I have gotten used to it, Mini Coopers come from a cold climates. If you use the correct coolant it should be blue, like blue Kool-aid, not green. Mini coolant is blue.

 

Yes, there is some oil in the system for lubrication. How much fluid have you lost? There isn't much in the A/C system.