when I drive with the o/d off, I get the chk engine light. every single time I read the codes, a new code appears and usually the old code I had gotten before does not arise again. anyone else experience this problem?
Check your chip install. Sounds like it mighta wiggled loose....or the connection to the ECU itself when you reinstalled it. The change in codes sounds fishy...like a bad wiring connection somewhere. Give that a look see.