BENZMAC - M103 idle drop modification
 

Hi,

I read a thread regarding removing the 50 rpm idle drop when the car is put into drive. I believe Benzmac stated it was for '89 and older M103 engines. Supposedly this alleviates some subtle blips in the idle.

I'd like to know how to make the modification to a '87 300E. It idles around 690-700 in park and it drops a bit in drive. Spark plugs, wires, cap and rotor were recently replaced. Injector seals were also replaced to fix vacuum leaks.

Thanks in advance for any help with the modification info.

Nolan

i had my 89 300e fixed at the dealership while my
car was in for a tune up. the drop in the rpm while
idling or when a/c is turned on, is a service bulletin
issue, hence, got it for free. my rpm still dips but
moves back to 700rpm all the time.

found the answer
 

I found the answer from another archive. Simple procedure and I was pleasantly surprised at the smoothness of the idle afterwards. 50 rpm sure makes a difference!

Here's the link:

http://db.mercedes.cx/mb/199705/0728.html

Nolan

i've read this article before. similarly, there are commentaries
against this band-aid fix. cannot recall main arguments
against it. just a warning, good luck!