Any new happenings? The other day, I was getting ready for a trip, and was listening closely to my car, and I heard a hissing. It turned out to be coming from an extra nozzle on the top of the EVAP charcoal canister. I'm guessing the EVAP system was in a purge cycle? I hadn't heard this recently, and I'm pretty observent, so I wonder if it straightened itself out? In addition, now when I crack my gas cap, i hear a bunch of air rush in. I'd like to maybe hook up a vacuum guage and see what kind of vacuum is in the system, but at the same time curiosity killed the cat and maybe I should just let well enough alone. I haven't gotten a single code code in the past two weeks, and I've driven about 1500 miles. Unfortunatley, I didn't do anything to actually "fix" the unknown problem, just did some probing to try to figure out how the system works (which is still unclear). Another mystery is raised by the hissing noise...where does it get this air supply which is above atmospheric pressure? I have a turbo, but normally the turbo is not pumping (especially when its just idling in the driveway), so the intake is under vacuum. I wonder if it somehow creates a pressure using a venturi with vacuum flow or somthing crazy like that???

Jason S
'84 850 Turbo, 205k