2.1 Waterboxer.....What is this sensor?????

I have recently dismantled my 2.1 waterboxer engine & found some type of sensor at the rear of the motor that was not connected to anything. The lead from the sensor was just sitting on top of the cylinder head. (out of a 5 speed manual transporter)

Now have purchased a second hand engine to replace my cactus engine & have found that it doesnt have this sensor at all, but it does have the hole in the crancase flange where it is supossed to go. (out of auto caravelle)

Question is what is the sensor for, do i need it, & if I need it what does it hook up to?





Thanks Guys.

Brendan

its the ignition trigger to the putor to tell it when to fire

was this only required on some models? Engine has been running fine without it. Or is it some thing that gives trouble so people are able to do away with them somehow?

Cheers
Brendan

Opps its similar may be its the timing pick up for the diagnostic test unit that no one ever used in Aussie

its diffentially for a timing pick up

but not sure on the T3 model how its used