My 96 Roady wagon has developed an unusual problem. It runs like a top, and has for the 4-5 years I've had it, and it is happy to run on regular gas. Anyway, in the last few weeks, when driving, under normal road conditions, all of the sudden the motor makes a rattling sound like pre ignition from bad gas, or gas with too low of octane. It'll do this for maybe 4-5 seconds, rattle a little, and then the service engine soon light comes on. After the episode, it resumes running perfectly with no rattling. The light will stay on for a short period of time, then go off. Has anyone head of or experienced a similar problem? Thanks. And, no Sprocket, I won't give you my car!!