transmission wont shift into overdrive on 1990 Mercedes-Benz 190E

transmission will not shift into top drive gear most of the time. sometimes when warm, it shifts normaly

Asked by for the 1990 Mercedes-Benz 190E
Adjustment of accelerator cable in transmission
My 1993 190E 2.3 has a simular issue. It will not shift into over drive at all. Runs great but burns a lot of gas because it will not shift into od. Help me please.nhjuuu