come to think of it actually, my car does seem to pop/burble when im sitting at idle. I know that its the maint light flashing, but its been doing this for a while now. I took it to the shop here in town and he said my timing could be off, so tomorrow im going to check it. It only does this popping sound when im idling and i practically vibrates the whole floor. Could be a exhaust leak, but i can still hear it coming out of the muffler its self.