I know that the computer on this car had some glitches that were cured with the later one. The idle is controlled by the control unit when the throttle switch is at idle. You can check this easily. I would suggest the 201 cd we sell in the partsshop. I have one and I own a 16v as well. There is the whole manual in there.
1981 280GE SWB
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
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