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Reluctor and 24 minus 1 cam trigger

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Ive been having some trouble with a bosch vr sensor and a 24 -1 trigger disc on the cam wheel of an RB26.

Setup is similar to the nzwiring kit. Does the trigger scope picture look correct? (correct distance between sensor and trigger disc)

It simply wont register any rpm value

TIA

 

4.jpg

Screenshot (3).png

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Yes your settings look right and the triggerscope looks close to useable.  For some reason the "missing tooth" gap doesnt look quite as wide as it should be to me - It should be twice as wide as a normal tooth spacing but it looks more like it is only about 1.5X so the ecu may not be happy about that (I assume it is counting up trigger errors?).  Almost like maybe the sensor is too big for the tooth size or something?  I would try giving it more air-gap to see if that makes the missing tooth gap more in proportion - you will prob need to reduce the arming threshold when you increase air gap.  

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Yeah, voltage is a bit too low in that one.  The gap maybe looks a bit more in proportion though.  Are your teeth a similar shape and design to NZ wiring?  same sensor?

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Heres a better resolution scope, i mesured the gap with a ruler on screen and it seems to be pretty much exactly the same width as 2 teeth spacing

8.jpg

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Unfortunately still no rpm, not even a hint. I have tried different sensor spacings but still no luck. This is my first time setting up a non-oem trigger so ive run out of ideas

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Does trigger 1 signal show "yes" in the runtimes screen when cranking?  Does the trig 1 error counter count up?

Can you attach your tune and a log of it cranking.

 

g1oMmqy.png

 

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I will upload a log and tune file tomorrow. I dont think i saw a yes next to the trig 1 signal now that you mention it. I'lll that check tomorrow and im also pretty sure the trigger error counter wasn't counting up. Thanks for your time trying to help me out so far mate.

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trig1 signal should show "yes" as soon as the voltage coming in on the trigger 1 pin exceeds the arming threshold.  So it is odd that is is not picking it up based on your scope pics being 0.5-1.0V.  Can you try it with the arming threshold set like below.

718n0wI.png

 

Can you also try this:

Set trigger mode to to Chev LS1.  do a store and power cycle.  Once powered back up change the triggermode back to multitooth/missing and reluctor etc as above and try again.  I have seen some cases where the trigger settings have not initialised properly and setting it to something completely different overwrites the bad setting and then it works when you change it back.  I dont see signs of that problem here, but it is worth a shot.

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Ok, Im starting to run out of ideas, but I just had another similar case from years ago pop into my head.  This was similar symptom where the triggerscope showed a wave form but the ecu runtimes showed no signal and no RPM, on that it turned out to be no ground connection between ecu and trigger.  For whatever reason there was just enough of a ground backfeed through other devices for the triggerscope to draw the waveform but there was no signal reaching the micro after going through the other conditioning circuits after the triggerscope hardware.  

The factory RB CAS grounds through both the ground pin/wire and the metal body of the CAS, so if that ground wire was broken, the factory CAS would still work, but you new sensor which has a plastic body wouldnt.

So as a test, just connect the cam sensor ground wire direct to the head/block and give it a try. 

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Would that problem still be an issue if in my case i have rewired the sensor completely? i ran new shielded cable from pins 42 and 52 directly to the sensor and then connected the negative wire and shielded braid to power ground  / pin 60. maybe i was not supposed to connect the shield to that pin or something??

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No that should be correct, but to rule out a bad ground connection somewhere please try back probing the ground pin at the sensor plug and connect it straight to engine ground with a small jumper wire.

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If you measure resistance between say pin 116 & the engine block, is it less than about 1ohm?  

If you unplug the ecu and measure resistance between pin 60 and 42 in the loom plug what resistance do you get?  Same resistance if you measure directly across the two sensor pins?

 

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Solved it finally! Whilst checking those pins i noticed a fault with my own wiring. Thanks for the help mate i wouldn't have noticed it if you hadn't told me to check those pins lol.

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