190e 2.6L sometimes dies going into drive or reverse

[herbivore]

Hi all, I recently purchased a 1992 190e, and it runs great except for when idling in gear. I saw the plug wires were arcing so I replaced them to little or no effect. Sometimes when I put it in reverse or drive it will die, but sometimes the rpms will just dip real low but the car will catch itself in time and bring the rpms back up in the nick of time. Same thing when stopping, sometimes it will stay alive but sometimes it just doesnt make it. I took the idle air motor off and verified that it was operational. The condition is a litle bit worse when the a/c is on. It idles @ 750-800 rpm in park or neutral, and idles around 500-550 when in gear (the times when it doesnt die)

Any suggestions would be welcome.

I should also mention that the accelration is nice and smooth, and really the engine purrs like a kitten at all times except idle.