This is a follow up to my "vibrating" idle problem. Just to recap, my 99 SOHC starts fine, runs great. While its cold, it idles in drive fine, even partially warmed up it fine, but when it reaches operating temp, the truck vibrates while in drive. I think it might be temp related so thats why I thought of the coolant temp sensor. Would that cause the problem? Could the O2 sensor also cause it, even though there is no CEL? I do not think its plugs or wires because like I said it runs great otherwise. I'm hoping to pass by Auto Zone today to maybe scan any codes.