Great pics Frank !
Nice input Stretch !!

Regardless of other systems and their different Bosch parts I am outlining my
findings on my motor.

On my particular M103 6 cyl in line, with the IAC connected, the idle is ~1500rpm.
With the IAC disconnected on two differenct IAC's, the idle drops to ~1000rpm.

With the Coolant Temperature Sensor connected, the idle is ~1500rpm.
With a cold start motor and a 39 ohm resistor to ground from the green/red
lead of my two point connection, the idle is right at ~800rpm.

My cold resistance of the Coolant Temperature Sensor is about 4,000ohms.

I have no idea what the M103 4 lead Coolant Temperature Sensor ohm reading should be.

FWIW, my cold start injector is quite different than the one I found in a 190E M103 motor. The IAC is the same.

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1992 940T

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