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Cam Fault with Full Sequential COP

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Hey y'all,
I'm a little stuck on the cam fault issue I'm having in Tuner Studio. Here's my setup:
Turbo Datsun 240z
Full Sequential/Coil On Plug
440cc Supra Injectors 
DIYAutoTune CAS Wheel in an '83 280zx Distributor
Wideband LC-2
DG508 Coils
Powerforce Damper
I went through all of the checkouts in the manual using the JimStim and JimStimX. Using the JimStimX, though, the correct setting for 'Second Trigger Active On' ended up being Falling Edge. When I installed the MS3 in the car I can only get it running with 'Second Trigger Active On' set as Poll Level. It idles but I get a Cam Fault in Tunerstudio.
I attached my msq and a composite log. Looking at the composite log and the physical CAS wheel it seems like the cam trigger should be aligned with the 11th tooth, but it's not.
I've read elsewhere that this fault is because the cam signal is on the wrong phase. I tried switching the CAS wheel and distributor (not the shaft but the distributor itself) orientation 180 degrees to no avail.
Any insight into what's going on here?




2019-09-13_16.46.35.msq 2019-09-13_16.04.34.csv

Edited by jkelly
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I tried adding 360 degrees to the tooth 1 angle to put the cam in the other phase per Matt Cramer's suggestion. This seemed to get rid of the cam fault during cranking, but now the engine will not start. The engine only starts with Second Trigger set to Poll Level in Full Sequential/COP but always has the cam fault. I've tried the other 4 combinations of Ignition Input Capture and Second Trigger Active On and the engine will not start. It fires a few times but then dies.


I've tried adjusting the required fuel up and down as well as the VE table and I still can't get it to start. 








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I'll follow up on this for archive/search purposes since it's been resolved. I did get the car to finally start using the following settings and in full sequential and COP mode with no CAM Fault and full sync. I'm not sure why it didn't start the first time I had this settings burned on the MS3. I did find my timing was off by 10º BTDC and it's possible the required fuel and VE table may have not been dialed in well enough.


Thanks to Matt at DIYAutoTune for helping out.




Edited by jkelly
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  • 1 year later...

I tried many other ways with the cam settings this is what worked for me. Rising and falling edge didn't ever work for me... my L28ET distributor is locked full clockwise.


DIY trigger wheel

MS3X full sequential fuel and spark

Coil on Plug Delphi D585 coils

set timing at 21 degrees idle




Edited by SHO240Z
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On 4/18/2021 at 9:39 PM, SHO240Z said:

Jkelly did you ever resolve your situation?


I did! It was just a matter of getting the correct settings. It was tricky because even with the correct settings it idled poorly due to other tuning issues which made me think it was wrong. Ill post my settings tomorrow for posterity. 

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