CEL as been coming on and going off.

Ir was on but I filled up and made sure gas cam was on properly, it went out This has happened 2-3 times. I did get a P0001 code but it too has gone out all by itself. I cleared today's illumination. Could my problem actually be the gas cap? A new cap is cheaper tha digging around in the fuel delivery system.

I also had a low threshhpld ont epass-side cat, but that's gonetoo, after a good 0-100 run

Thoughts? Comments?