While sitting in a drive-thru yesterday I noticed a "thump thump thump" feeling and my truck was slightly surging when I let off the brakes. I shut the truck off and restarted it with the gas pedal floored so it would not start, just would keep cranking and I noticed the starter has a different sound now. Sounds almost like one cylinder has low compression I don't think I did anthing to hurt the engine. It literlly just appeared yesterday. I did have to gun it pretty hard yesterday on the freeway to pass a truck and sometimes I get detonation I hope I didn't damage anything. Engine is a 4.6 and has 184k miles well maintained. Ill go ahead and replace the plugs and wires but im not sure about the compression until I do a compression check. Should I continue to drive the truck? It doesn't feel like a totally dead cylinder but there is a noticable idle change but seems to smooth out at higher rpm's.