Anyone know what this thing is on the back of my 260Z speedometer?

The red wire goes into the housing and to the center bit that goes around and around.

See pics.

Pic number 2.

Yeah, that's the thing I got. It has a black plastic sleeve going inside, with what 'feels like' a cable inside it.

The wiring diagram shows something labelled "Amp."

OK, now we know what it does on a carbureted 260. The question remains what does it do on a FI 280?

Originally posted by TomoHawk

Yeah, that's the thing I got. It has a black plastic sleeve going inside, with what 'feels like' a cable inside it.

The wiring diagram shows something labelled "Amp."

Yeah it has a wire going inside to the big round bit that goes round and round. I think it has magnets on it, and the magnetic pull makes the needle register a speed.

Its probably some sort of sensor to guage car speed.

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