My Grandma has a 1992 Buick Regal with a 3.8 motor. The car has been having issues of late and the newest one is that it now has a sluggish start. Once it gets going its fine but its really slow to get going. She took it to a mechanic and he said it was the cars computer. So instead of her taking it in for 400 dollars for some BS excuse I told her I could reset her ECM and see if that helps. But I think its a build up of junk from use within the engine. What do you think? Could it be a build up in the exhaust or cadillac converter or what?