My 99 deville with just under 109xxx miles just suddely started jerking, hesitating, or whatever one would refer to it as yesterday. It idles fine, and run just fine. This only happens when you gun it and make it work. I have been reading posts of all sorts from wires, to plugs, to MAP sensor, to even Head gaskets.

About a week ago I took it out and showed a couple of guys what a Northstar could do. We were doing a 110 when we passed two Sheriff's. Ran great and has been up until now.

Comments and suggestion?