1999 Chevy Astro rough idle

Hello Folks,

The aging work van developed a vibration which at first I thought was the front brake pads sticking- it was late winter.

The vibration was primarily present in the morning after start up but has lately been present during the day also.

Today while driving on the high way to a repair job the the check engine light came on and continued to flash rapidly. In the past it would come on, flash several times then simply stay on. The light would usually be off the next time I started it.

As I exited the highway I noticed a very hard vibration as the engine spun down to an idle, the engine would not stay running at idle and it was hard to restart.

I drove home but am concerned about driving further, although I do need to keep the business going.

New plugs, wires etc. At 100,000 miles.

Thanks,
Ken