I asked this question in an old thread but I think it got lost. Can Anyone advise how to wire this? I have an 81' 300SD and the wires from the CPS have been clipped off and put to the side.
I just finished reading the DIY article on changing the CPS, and while it tells how to replace it , it only deals with the sensor end.

Now the question is what does this thing do? Mine is not connected to anything at the other end. Any idea where this wires into the harness?

The car seems to run ok, but I wonder if the efficiency is off . The only real problem with the car is the tranny seems to shift funny( not shift up through the gears unless you let up on the accelerator) and flare (slipping?) during normal acceleration through the gears. I have gone through the vacuum lines, and valves with no real effect on the shifting. I am wondering if this is related to the CPS not connected. Any help appreciated.

That is only for the tachometer.

There's no computer or anything looking at the CPS.....I want to replace mine as its the last part of an unending saga trying to get my tach to work. Gauge and amp have been replaced, and it has 13.8 volts at the plug into the gauge, and at the amp....so it HAS to be the sensor....

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My tach is also not working but the sensor for that is on the front crankshaft pulley, i think. The sensor I am talking about is on the back of the engine,on driverr's side , right where the tranny bell housing mates with the engine. It has two wires coming out of it that, in my car , someone has cut free and then left the pig tail clipped to the firewall.

has your engine been changed out? that is the way 85 617's send cps to the tach, and I think there is some interaction for the egr or something, but not for the transmission. and that would just be for an 85, not your car. that explains why the wire is cut, there is nowhere for it to go on an 81.

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