wiring diagram pre-glow -88 300D
 

someone having a electrical wiring diagram on a -87 300d? with om.603.xx engine? i would love to have one... i always have same glowtime hot as cold... and my car is converted to a diesel so i love to check the wiring for faulty things... :)

The wiring diagram in the 126 shop manual isn't very useful in that regard. It shows a coolant sensor input into pin 6/white wire. It also shows something like a potentiometer with words to the effect that as temperature increases resistance decreases with a reference ground at pin 4/brown. These wires are in the connector that doesn't contain the wires that go to the glow plugs.

Sixto
91 300SE
87 300SDL
83 300SD