Anyone know what this is?

[Zephyyyr]

I got a set of spark plug wires but it seems like it doesn’t have the same wire that connects to the #6 wire that goes to the distributor. I’m wondering what this is? :/ I’ll post some pics below.

Btw.. I own a 1989 325i.

[Zephyyyr]

Also what looks to be the wire the connects to the coil is unattached from the wires.

[AndrewBird]

That's a pulse sensor. Kind of like a low tech cam position center. Early model cars had them.

And yeah, car won't run without the coil wire.

[Zephyyyr]

That's a pulse sensor. Kind of like a low tech cam position center. Early model cars had them.

And yeah, car won't run without the coil wire.

Thanks for the response. So I have the early model? I thought for some reason that was 1988 and under?

[Zephyyyr]

That's a pulse sensor. Kind of like a low tech cam position center. Early model cars had them.

And yeah, car won't run without the coil wire.

Also I have another question. Is the pulse sensor needed? Because even tho my coil wire is unattached I can still connect it to the distributor just won't be a part of the actual harness. At least I am pretty sure I can do that lol.

[TobyB]

It's used by the ECU on the M20b25 to tell it which batch of 3 injectors to fire.
So it's a 325i/is feature, goes with the front crank position sensor.
And yeah, kind of... afterthought- looking.
You don't HAVE to use it- it'll help idle and emissions a bit, is all.

t

[AndrewBird]

Thanks for the response. So I have the early model? I thought for some reason that was 1988 and under?

My mistake, it's not just early models, it's all 325i's. HEre is more info:

https://www.r3vlimited.com/board/showthread.php?t=239743

Basically you can run with out it, but it is better to have it.