No one can confirm conductor plate is your problem. It is likely but no guarantee. I had the same problem with my CDI not shifting out of low or not moving at all. If I turned off the car, waited for awhile then the car will shift until it happens next time. I changed the conductor plate buying the cheapest one from eBay and the car is still running after 25k miles.

You mentioned you changed the conductor plate before so it is unlikely your problem. It could be the solenoids but who knows. Don't want to disappoint you but it is what it is.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.