have someone step on the throttle while you look at the linkage as it moves. odds are good you will see what is wrong if it's linkage related. likely the bolts that hold the swivel parts to the valve cover are loose.
if everything moves smoothly, and it does not look like things are broken, post back.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I'll do this tomorrow morning and get back. Do I do this with the engine running? Link to what the linkage looks like? I'll do a bit of searching.

digi

With the engine off!

Once the helper "floors" it, grab the linkage under the hood and see if you can move it more in the "go" direction.

Super-standard with a new-to-me '80s diesel MB car is to pop ALL the linkage balls loose, clean them, then lube with a drop of ATF (stone age, yes, but MB spec).

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James Marriott
2003 Buick Regal
1983 300D (228k, frau Auto)
1996 Suburban K2500 (192k, 6.5 turbo diesel/4WD towmaster 10,000)
www.engineeringworks.biz
1987 300SDL junker 170k
1982 300SD junker, 265k