Not getting any trouble codes. Throttle cable moves freely. I have gotten a few whiffs of a rotten egg smell from the exhaust but not very often and its only after high rpm's from passing someone. The engine accelerates fine with little to no throttle. I was almost thinking it has something to do with moisture getting into something because it only does it when I leave for work at 5am. These cars do not have a distributor that can crack and allow moisture in and I was wondering of the coil packs could somehow get moisture in them? Could it have anything to do with the cold air intake that is on the car?