Ok new development...total mystery to me but maybe some of you smart guys can figure it out. So been trying to track down intermittent idle problem (low RPM and trying to die)...read about a zillion posts...carb, solenoid, fuel pump, EGR, vacuum leak, you name it. Kinda settled on sticking EGR since it was so intermittent...could drive it several days in a row purring like a cat and then boom no idle. Tuesday I drove it to work and when I rolled into parking lot...rough, dying idle. I kind of got frustrated and stomped on the gas to rev it up...boom big backfire from exhaust. And lo and behold idle smoothed right out and has been smooth since then. Maybe a coincidence. Any ideas on why that would have "fixed" the problem??