Symptoms of a rear air bag leak/how low does the suspension go?

[Ricky Bobby]

Guys, been dealing with air suspension issues recently and wondering if someone could shed some light here. My front air struts were replaced in January 2012 with Arnott units, work excellently. I also replaced my compressor as it was burnt out of spec at that point (had I known about the seal fix to get the compressor working I would have went that route). I don't know if the previous owner ever replaced the rear air bags, but when my fronts were replaced, the indy shop said they tested the system and the "rears were fine".

Well fast forward a year and a half and what I think might be ride height issues turns out that my left rear corner is sagging more than the right rear. I wanted to let the X sit for 24 hours so I could check to see if it lost any more height but it is already fairly low, approx. 27 1/4 inches from rim flange to fender (20" wheels), whereas the right rear is about 3/4 inches above that.

My question is, when the front air struts were blown, they literally were basically touching fender to top of tire, until the car started and they could be pumped back up when the car is running. Correct me if I'm wrong, but even if the rear bag or bags are leaking doesn't the rear shock only allow them to "sag" a certain amount (unless calibrated to be lower than that) because of the static load on the rear suspension? So even if they were blown completely they wouldn't be riding completely on top of the tire like the fronts were?

Oh yeah, and I've had a random SELFLEVELSUSP INACT errors the past week or so, they would pop on and go away, but last night when I went to get take out, it popped on and stayed on, so I can't even pump the car up to offroad height to get a better look at the bag.

Got under the car last night and looked at the base of the bag with a flashlight, the right rear doesn't show any hairline cracks that I can see, all height sensors look fine, but the left had a few tiny small cracks, I will test with soapy water tonight to see if I have bubbles (although if the corner is lower that will tell me enough)

Basically if I have a leaking rear, I'm trying to catch it as soon as I can to avoid blowing out the compressor (again).

Thanks!