Missing/Surging when cold...

I'm sure I'm missing something, see if ya'll can help... I had some work done on the Jeep (I hate other people touching her!) and have had distributor problems since. To date I have reindexed it (was 1 tooth off), replaced plugs, wires, cap, and rotor. Before the reindexing it would do this all the time, that fixed it for a few months, but it's shown back up.

For about the first 15 miles in the morning it will surge badly at 3k rpm. The last couple of days it will even do it at 2k, which makes for tough driving. Where's a good place to check? Thanks guys,

Brent

Anyone have any ideas on this one? It's a 5-speed by the way. Could it be a bad CPS? Thanks!

Could be a number of issues. What year/vehicle are we talking about? Vacuum leaks that seal when warmed up are common (EGR sticking?)

Oops, sorry about that...it's a 91 XJ 4.0, 5spd. Could be a vacuum leak, you think that could cause a violent jerking like this?