$17 fixed it. Don't forget the WIRES
After spending $275 for an ignition coil I may or may not have needed, what fixed the old beast was a $17 set of PLUG WIRES!!! and 35 minutes of my tiime.
I didnt have time to fix the Bonne so I dropped off the car at the local Chevy dealer and told them of the rough running during cold start. Car would run fine after reaching temperature however.
Two days later, same thing !!
Did all the recommended throttle body maintenance stuff recommended by our great members - IAC cleaning, throttle body cleaner, EGR, etc etc etc.
I would recommend that if your plug wires have over 35,000 miles, change them out. Or most definitely change them when you put in new plugs. Wish I had the $275 back.