Yet another intermittent stallling problem 190E 2.6

[hornbrod]

Wife is complaining about intermittent instant stalling on the 92 190E 2.6, usually when slowing down and making a left turn. Has only done it once for me, but I don't drive it too much. The car had been slow cranking, so I replaced the battery (it was due). Cranks fine now (three weeks later) and battery voltage w/o engine running reads 12.6V, w. engine running charging voltage w. full load applied (lights, A/C, high blower, etc.) is around 13.6V. So it appears the battery and charging is okay. Replaced the OVP with a known good one (not new) from my other 190E, no help. Cleaned all ground and hot terminals I could find w. contact cleaner, no help. Pretty sure this is electrical since the stall is instant. Stalling is worse in warmer weather. Always starts back up instantly. I'm thinking possibly cleaning the Idle Control valve and checking the operating voltage next, then checking for a vacuum leak (hope not). Am I on the right track or missing something obvious? Thanks for your help as always.