MX-5, as usual, you were right... but it was not loose, it evidently had failed...
took your advice, cleared the ECM, made sure cap was tight, light came back on with-in 1 mile...
tried it again, cleaned the gas cap flange, wiped the tank filler tube, cleared the ECM, light came back on in a mile or so...
took a chance, stopped by a DC dealer, bought a new gas cap, changed it and again cleared ECM, no light in over 150 miles...
Thank you Sir....
