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Yep looks right. It will measure as ground but there was someone who connected it to ground and that made it run poorly, I think less signal went through the pcm. It should be direct like you have from pcm to module.

Yeah okay. Back to square one of not really having any idea where to go from here. Short of getting a scope and looking at it.

antus wrote: ↑Fri Nov 29, 2024 6:51 am Yep looks right. It will measure as ground but there was someone who connected it to ground and that made it run poorly, I think less signal went through the pcm. It should be direct like you have from pcm to module.

Yep that was me.

My guess in this instance is that the wheel isn't think enough to produce a decent signal.

Yeah that was my thoughts to. I've made it as thick as possible in the space I have which is just over 3mm and that's the max width I can make it

Well I got my hands on a scope to have more of a look. Will hopefully get onto hooking that up in the next couple of days

So I tried hooking up the scope. It definitely doesn't look right. I tried swapping the polarity. I can see each tooth event except the reference tooth pretty well. Is it simple just the diameter of the the trigger wheel being to small?

It's roughly 180rpm cranking speed from what I could work out from the waveform.

Anyone have any more ideas?

The wheel on my RB30 is that small. How is the run out on your wheel?

Going off the peaks on the scope it's pretty good not a heap of variation. The sensor airgap is 18thou on all the teeth from what I measured maybe a couple were a tad tighter then others but I couldn't get a 19thou feeler gauge in them so must be hardly any

I cant say for sure, but I agree the signal on the +1 notch looks too low. Especially on the low side it (first pic) it barely crosses over the 0v mark. The flat space between the notches also looks up to 2x different between different pins in the trace but its hard to know if that's a problem because I assume your cranking the engine and the crank speed will vary quite a lot too, so from that the +1 signal looks like the most likely problem.

Yeah that's what I thought too. But unsure how to go about fixing it. The trigger wheel teeth are like the ones on the template but maybe not quite as high. It's like the sensor isn't picking up the slot between the teeth well enough? Given that all the the others seem to have good signals I don't know why it's not getting that one well.

As far the different in crank speed between pulses could just be from cranking on the starter but I won't know until it runs I guess. The teeth are spaced accurately I hand filed it to match the template perfectly