My little 190e has had a loping problem for awhile now, and It seems like I've ran out of ideas. When I bought this car, I put another fuel distributor on it (it had a running probelm I thought was fuel related). At any rate, Between the timing, and the enrichment mixture, I cannot manage to get this engine to stop surging.
I can adjust it up to 1,100 rpm at idle in park, and in drive it will drop down to 850...and runs fine. Take it for a spin (gets warm), then come to a stop sign, and it starts to surge between 850--1200...I guess the system is trying to adjust it self, but to no avail. Sometimes I keep one foot on the brake and one on the gas (automatic) to keep her running smooth at stop lights.
Any Technical advice on this matter would have me smiling for months to come.............Thanks in Advance...S in VA

Have you looked at or changed any of the relays. Particularly the Overload protection relay (OVP) located behind the battery with a fuse on top. Check the fuse. Or replace the relay if it never has been replaced. The fuel pump relay next to it should also be checked.
As some of the techs on this site would tell you a good diagnosis by a competent shop could save you the time and expense.