Hello all. I have a 99 7.3. It has been running great. 207k on it. Also has a Ts 6 position tuner. It just recently got cold here in Western New York. The other night I was working in my shop and the truck was out side. I started the truck to warm it up, and set the Ts 6 to the high idol setting as to not just have it low idling. About 45 min later I shut the truck down and plugged in the block heater. Now it is 4 days later. I started it up and it has a low end sound like a lump. It runs but at low idol the truck shakes. What should I be looking for. Thanks in advance for any advice!