What does this likeliy mean? While driving this morning on the highway and with no warning the check engine light came on and was blinking. Everything I have found indicates the potential for a critical failure of the engine. Is this accurate? I immediately pulled over and didn't find anything out of the ordinary, shifted into N and P, then back into D (I was only about 400 yrds. from exit) and the light went off. I left the truck there and not sure where to go from here. I read somewhere that this indicates a coming failure of the catalytic converter??? Any help would be appreciated.