Vapor Purge system

[CharlesWDavis]

A bit of recent history of repair work by Dealer on my 1999 Mazda Miata.
08/31/05 Miles 52,099 Over heating. Replaced radiator.
10/31/05 Miles 53,269 Fuel smell when driving and sitting in garage. Recommended placing spare in plastic bag???
06/13/06 Miles 56,990 Replaced A/C condensor & dryer
08/08/06 Miles 57,851 Overheating, replaced thermostat
11/21/06 Miles 59,531 Overheating, Intake clogged, removed and installed intake and EGR ports.
07/09/07 Miles 62,500 Rough, variable idle (750 to 1,200 RPM), and seems to miss during street driving and overheating sufficiently to turn off the A/C, it stayed in repair facility 18 days. Replaced bunches of stuff, including timing belt while so much work was being done.
08/13/07 Returned to service facility as there was no change from previous and 11 days later, the problem was solved and road tested OK. Replaced fuel filler pipe and cap. I drove to the first traffic signal, and the engine idle varied worse than ever (1,200 RPM to almost stall out). I made a u-turn and they have had it since 8/24 with no valid diagnosis.

Any thoughts?

[CharlesWDavis]

The problem has been solved!!!

After 33 days in the shop, they finally replaced a "roll over valve!"