On a normally aspirated 606, there are two different flap-like devices in the intake tract; one of them they may be mistakenly called a throttle body due to its appearance & function.

It is the first one in the airstream, at the passenger side of the engine and attached to the large crossover tube that leads to the intake manifold. (The other flap valve is inside the intake manifold itself, and is used to tune the intake tract resonance for controlling the power at low vs. high RPM’s.)

The first one acts like a throttle body and apparently controls the amount of air as well as somehow regulating the amount of EGR being drawn into the engine as well. (yes, there is an EGR valve, but if this “throttle body” is closed, it will place a tremendous vacuum on the EGR port and increase the amount of EGR flow.) That all being said & done, it doesn’t make much sense that there would be any failure of that unit in conjunction with the wiring harness. It is controlled by an electrical connection/solenoid via a vacuum pod that actually does the physical movement of the valve.

Also, the NA 606 in my 124 does use a cable & linkage to the IP – it is not electronically controlled (except for the idle speed apparently). I think that the later ones (turbos only???) do use an electronic control for the IP.

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Current rolling stock:
2001 E55 183,000+ Newest member of the fleet.
2002 E320 83,000 - The "cream-puff"!
1992 500E 217,000+
1995 E300D 412,000+
1998 E300D 155,000+
2001 E320 227,000+
2001 E320 Wagon, 177,000+

Prior MBZ’s:
1952 220 Cab A
1966 300SE
1971 280SE
1973 350SLC (euro)
1980 450SLC
1980 450SLC (#2)
1978 450SLC 5.0
1984 300D ~243,000 & fondly remembered
1993 500E - sorely missed.
1975 VW Scirocco w/ slightly de-tuned Super-Vee engine - Sold after 30+ years.