This is on my '93 300e. I have searched as many threads here and the other ususal MB sites, but have not found any consistent answers as to why this is happening.
The transmission was operating normally, but suddenly quit shifting from 2nd until around 4,200 rpm. When the transmission is cold it will sometimes shift in the 3-3,500 rpm range, but once hot it's always over 4K. When it does shift, it tends to go to 3rd and then immediately to 4th. The car drives fine until I stop at a stop sign or light, then we go through the whole high rpm shift routine again.
Initially when I tried to manually shift from gear to gear it wouldn't respond, but now after a fluid change I can shift down and up between 3-4.
As noted I changed the fluid and filter. I've disconnected the kick down switch, and checked the adjustment of the bowden cable. I even disconnected the switch that delays shifting during warm up, but none of these seem to have any effect.
I found one thread where another owner had similar issues which were resolved by changing out the modulator valve. This doesn't make sense to me as I undertand that impacts the crispness of the shifts, but I didn't think that would effect the timing. I was thinking it would be worth replacing the K1 spring assembly as I understand that controls the 2-3 shift.
Any other thoughts, or suggestions are greatly appreciated.