Hi Frank,

In reading your idle symptoms, your saying that the idle smooths out
once some warmth is in the engine.  If this is so, My van had a similar
issue .

 On a  cold soak start up, base fuel pulse is modified by the Temp I ,
air temp sensor.  According to Darryl Boelher the ECU guy, the ECU
richens the fuel pulse map according to air temperature on cold start
up.  Darryl said that the amount and temperture of activation varies
depending on which ECU and  production changes.  Mine is the Bosche 22 D.

On my model the TEMP I gets  ignored until 0 degrees or so centigrade,
and then the ECU begins the enrichment process.
Anyway, for the first minute or two on below freezing days, I would have
a chugging erratic idle and then it would smooth out.. Cause was the
Temp I sensor, until the Temp II was warm enough for the ECU to use
coolant tempterature map.

Sincerely,

Mark Keller
91 Carat

Ps I'm on digest, so pmail me to dialoge,