Hi, I have a '72 350SL 4.5 (107.044). The engine was pulled and re-installed by a "mechanic" who was replacing the motor and transmission mounts. After a very long time, (over a year), I took the car back and I am now in the process of getting it running again. So far, I have found a bad distributor cap (the guy broke it) and three bad injectors (they were stuck open). I replaced the cap, and installled all new injectors and seals. My problem is with the MAP sensor, which was not connected when I got the car back. Although the plug to it is keyed, the sensor itself (Bosch 0 280 100 100), is not. I need to know which way the plug goes into the sensor. The plug is curved on one side and flat on the other. Does the curved side go up or down? The wiring harness is color coded, and the sensor body is numbered. If there is a manual somewhere that references the numbers on the MAP sensor to the color coding of the harness, that would help as well. I am afraid to plug in the new sensor I have ordered without knowing this. Help!

I'm pretty sure it doesn't matter which way the connector is hooked. The two outside terminals are connected to one coil of .5-1.0ohms resistance. The middle two terminals connect to a coil 3-4ohms. Since the way the device works is to pass a field through one coil and measure the iductance off a second coil that has a variably inserted core (the core moves in and out under the changes in manifold vacuum). One coil imparts the field to the core and the other one oicks it up depending on how deep the penetration. Since both fields would reverse the inductance between them should be the same.

Anyway the gy/gn goes to term #7 gy/bu to #8 the gy/rd to #10 , and gy/bk goes to #15. Thats how the wiring diagram has it anyway.

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Steve Brotherton
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician

Thanks a lot, Steve. Hopefully, this will get me back on the road
Thurman