300-24, saloon and coupe, E300 24 valve diesel estate
Undo the under tray under the dash and lower. Look at the pedal and you will see where the cable goes though the bulk head. On that bit of cable is an adjuster. Usually a cream coloured knurled ring. Turn it clockwise to tighten and anticlockwise to slacken. There should be 1mm of slack at spring on the other end of the cable where it goes though the actuator.