The 606 turbo engine (as found on the 98-99 E300Ds) is drive by wire. It is not like the 603's EDS that just helps with idle management, the computer runs the whole show on the 606. The go pedal is a potentiometer that tells the computer how much speed the driver wants, and then the computer decides how much to pull the rack. It ties into the ASR/ABS/ESP/cruise control systems as well via CAN bus.

I don't know if the 606 DBW pump can be reworked to a mechanical pedal. If so that might be an option.

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The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech