You guys offered me some promising advice regarding my 190E 16-Valve's idle problem that no one can figure out. With both of you suggesting the air flow position sensor. I looked back at my records and one of the shops did break things down to the throttle body, to check some things including the air flow sensor. Anyway, Doc, I live in Atlanta and would like to bring the car to you if possible for diagnosis. Let me know where to find you.

Sincerely,

Kurt

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[M.B.DOC]That is a COMMON 16V problem! 99% of the time the problem is the air flow position sensor! Have replaced at least 20 of them for that exact problem.

MB part number 000-074-23-14(complete housing w/sensor) with a list $675! takes 2.5-3 hrs& requires several other parts[/QUOTE]

[MrCjames]
I'd have to agree with DOC. If you would like to be certain that it is the sensor conduct the following tests.

Disconnect the sensor and measure the three wires for voltage, one wire will have roughly 5V. This is the reference voltage to the sensor. Measure the two remaining wires for a Ground circuit. The third wire is the air flow position signal, the feedback voltage to the control unit.

Now that you have an idea of the three wires and their purpose reconnect the sensor but leave the pins somewhat exposed so they can be probed with meter leads. With the engine running measure the feedback voltage signal, specification is approximately .5 V to .9 V.

Happy motoring to you