I need to get my 87 325 running again. It starts and runs extremely rough. Basically it seems like the ecu is not getting a tach signal (hard to rev, no rpm indicated on the gauge).
So I think that I am not getting a tach signal to the ecu; but can't figure out how to test it. Revlimited and google have tried, but no dice.
Sooo, other than buying a replacement tach plug wire, how do i test this thing?
Thanks
In reply to Timeormoney:
Set a multimeter to AC voltage. Lots of tach signals are square wave and the AC setting will pick up something, usually between 1 and 6 vac, varying with revs of course.
Hope this helps...
later, Matt
Thanks! I was wondering if the AC setting would pick up the 5v square wave, will give it a shot.
If that doesn't help, I am just going to video the idle and have a "watch the video, guess the problem" post
it should read the 5v sq wave... if not is there an electronics shop near by that would let you hoop up a o-scope ?
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