I doubt that it is anything like to do with the idle speed
Doesn't it sound more like you have a glow plug that may be bad or on its way out? Real easy to test with an ohmmeter.
Thats about all I can offer (based on a glorious 6 months of mb diesel experience).
later
__________________
84 300TD - 235k - Farbe "Surfblau" bought at 213k
87 300SDL - 131k - Farbe "PimpGold" bought at 115k
00 Klepper Faltboot Expedition Double
|