If you were having a fuel or ignition problem, I'd expect the car to stall or have some other operating problem when you pressed on the accelerator pedal. Since you're having no change, I'd strongly suspect the linkage isn't actually moving the throttle plate.

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Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]