If it's not the kickdown switch, it may be the kickdown solenoid in the transmission body. It is located somewhere near the back of the tranny. Mine was stuck once when I first got the SDL running. It was like it only had first gear and wouldn't shift into second. I had to stomp on the kickdown switch a few times before the solenoid unstuck.

Haven't had a problem with it since.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)