Engine sputtering/mis-firing?
 

I had started a thread a while back inquiring about what I preceived to be a "cold start" problem. I don't think that's what the problem is. What happens is; that many times when the car is first started, it misses and sputters as if there were some sort of electrical problem. It'll continue to do this for 10 minutes or so. Then it'll clear up for say, another 10-15 minutes. Then it starts again. Maybe goes for another 5 minutes missing and so forth, maybe 10. Then it'll clear up again. It seems that the problem is worse on initial start up and especially when it's cold and/or damp. But it does it, none the less, even on warmer days, so I can't say in all honesty now that it's a "cold start" problem. It seems to be intermittant, though. Sputtering, stumbling at idle and acceleration. Even cruising.
Now, does anyone have any clues? We only use premium gas.
Thanks

...and this is ????????

'89 420 Sel