its the seat switch. that was the problem with my old 300e. I thought it was the motor messing up, but it turned out to be the switch.
1987 mercedes 300E
1995 e320 conversion(hated the 300e grill)
Monochromatic Paint (Custom Blue)
Flat Badged (front)
custom "carbon fiber" console
18 inch HP EVO rims
Sold! Now I drive a Monte Carlo SS