[aerohead]

A friend with a Rav-4 "developed" a check engine light WITHOUT a scangauge.No dealer or independent shop could ever isolate the problem.My friend ended up sticking some electrical tape over the idiot light as it was a constant distraction.The vehicle was later sold and the second owner continues to drive it.I like the "grasping at straws" analogy,as local certified technicians appear impotent without their "codes." The scangauge could easily have absolutely nothing to do with your cars problem,as I understand they merely interrogate the system.