Hi, just joined up here, so a newbie. Does anyone know of a good web page with an overview and pictorial diagrams of the mercedes hfm injection system for my car so i can study it.
I just purchased a 1993 300e 124.028 engine is 104.942HFM with hfm fuel injection system and it's having idle speed regulation issues(fluctuation between 0 and 2000 rpm). the just off throttle idle position with load is fine, such as putting into gear and driving off..no hesitation or misfiring with plenty of pulling power., it's just the unloaded idle that is a problem..seems like a vacuum leak to me but visual doesn't reveal any and i am unfamiliar with this system and i like to know the system before replacing parts. An overall block diagram with descriptions would be helpful. Thanks in advance.