My 00SS M6 has developed a {stumble] between about 5100 to 5400 rpm .I recently installed mac headers and orp so the first thing i checked was the new TR55 and accel 300+ wires. All good. Fuel filter is new. After about 5400 it pulls thru it and pulls strong to 6000. Put it on a scan master for the LS1 and it showed a steady 28 degrees spark and no knock retard. O2 were a little rich @910. When the car was cold 162 degrees it was fine, but after it warmed up to 192 it started to {stumble ] again. Possibly a coil? Any help would be greatly appreciated. Paul

 

ttt

Anyone hear of coil packs going bad??

 

F1 havent run into this yet but a coil pack break down would be load sensitive not rpm sensitive. If you spray light mist of water on suspect coil pack and then load it up you may be able to invite condition. Give it a shot.

 

check the egr o ring ( i think you have it, but not sure) it caused the exact symptoms on my car.

 

I had to change my EGR to 98-99 style to make my headers work. That could be it. Thanks for the input.

 

TTT

 

Removed, reinstalled the EGR ring. Made three passes, the car ran perfect and pulled flawlessly to 6000! I am cautiously optimistic that it is cured ! !Dirty Z YOU ARE THE MAN! <img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" /> I think im ready for the Viper, Vette, and F-Body shoot-out in bradenton Fl on Feb 10th.