I'm sorry, but I have no idea.

My first instinct is to check the level of your trans. fluid.

My E320 Cab has same problem
 

I am told my car needs a retard upshift dleay valve and the dealer wants to charge me $1200 to fix it. What do you think? Seems like you had the same problem a few years back.

Are they insane? I would simply take it to a trusted independent MB Shop.

Steve

I recently had my upshift delay actuator and one of the O2 sensors replaced by the dealer to correct CEL and poor gas milage in my 94 E420. After the service it seems to delay all shifts alot when cold, still some delay when warm compared to how it used to shift. This car does not have 2nd gear start.
1. What temp. does this delay work off of? Engine coolant? Trans temp? Cat conv.?

2. I frequently must turn onto busy streets and highways so i was wondering if there was any way to disable the delay or trick it without setting off the CEL.

3. What effect does trans fluid level have on shifts? I suspected the dealer overfilled the trans so I sucked some out which seemed to improved the shifts. but when I check it the fluid is always way above the mark on the dipstick and I feel really stupid for not being able to determine how much fluid is in there.

FYI, to replace my delay actuator at the dealer it was only around $400. 200parts 200 labor roughly.

how funny and strange when people invent things about these type of problem lol.