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Gen 4 LS - no crank trigger

Posted: Thu Apr 27, 2023 8:22 pm
by ykill
My crank trigger isn't received by my Proteus.
I'm not really sure what's happening.
Cam signal is received.
I moved my crank signal from digital 1 to digital 5 and updated my tune accordingly but still nothing.
I thought that I had and issue with wiring so I tried every positions possible.
Sensor is receiving 5v (in fact it's the same as the cam sensor)
Ground is good
I don't have an oscilloscope to confirm that I get signal from the sensor.
Sometime, when playing around, I can get signal for one or two revolutions.
Should I add a pull-up like I had on my megasquirt?
Any idea on what could cause this issue.
I'm pretty sure that it was working when I only had ETB, CAN and Cam/crank plugged in.
I changed firmware version between then and now, should I go back to the previous version?
I've been working on this issue for the last week and I'm out of idea
I'm sooooo close on starting the car 🤬

Re: Gen 4 LS - no crank trigger

Posted: Thu Apr 27, 2023 8:48 pm
by mck1117
Proteus has internal pullups on the digital inputs already.

Do you see anything on the trigger logger tab in tunerstudio?

Re: Gen 4 LS - no crank trigger

Posted: Thu Apr 27, 2023 8:56 pm
by ykill
Yeah, only the cam trigger

Re: Gen 4 LS - no crank trigger

Posted: Thu Apr 27, 2023 9:24 pm
by AndreyB
Many digital multimeters have Hz frequency mode, probe on PCB on back side of connector if you see frequency while someone else is cranking?

Re: Gen 4 LS - no crank trigger

Posted: Thu Apr 27, 2023 9:29 pm
by ykill
I will try that tonight!

Re: Gen 4 LS - no crank trigger

Posted: Thu Apr 27, 2023 9:31 pm
by mck1117
Has this crankshaft/sensor combination run an engine before?

I ask because the 24x vs 58x trigger wheels need a different sensor (24x black sensor, 58x grey sensor). If they're mismatched then you'll get a crappy signal or no signal at all.

Re: Gen 4 LS - no crank trigger

Posted: Thu Apr 27, 2023 9:40 pm
by ykill
mck1117 wrote: ↑
Thu Apr 27, 2023 9:31 pm
Has this crankshaft/sensor combination run an engine before?

I ask because the 24x vs 58x trigger wheels need a different sensor (24x black sensor, 58x grey sensor). If they're mismatched then you'll get a crappy signal or no signal at all.
Yes, it was running in my MS3 before, signal was flawless

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 12:50 am
by ykill
AndreyB wrote: ↑
Thu Apr 27, 2023 9:24 pm
Many digital multimeters have Hz frequency mode, probe on PCB on back side of connector if you see frequency while someone else is cranking?
I tried to do so but it gave me khz instead of Hz (auto adjusting). It was acting weirdly so I'm not really sure this function worked correctly on my multimeter....
I'll try to find an oscilloscope

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 1:56 pm
by ykill
I attached a trigger log
It seems that I need to crank for really long until it gets recognized.
Signal wires aren't shield, could that be the cause?

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 9:13 pm
by ykill
Little update
Signal is way better.
It seems like removing the fan wires helped a lot.
I removed the CEL wire as well
but rpm is jumping a lot and I'm getting a lot of sync errors, if it was a VR, I would have thought that the starter is making noise since the wires are next to it.

I'm a little lost with that problem.

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 9:20 pm
by mck1117
where do the sensor's ground and power wires go?

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 10:05 pm
by ykill
5v is coming from the white connector and I don't remember exactly but I'm pretty sure ground is going to sensor ground on white connector as well

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 10:06 pm
by mck1117
I'd make sure that the ground wire is going to the ECU's sensor ground, and isn't connected to chassis/engine somehow. An easy test is to unplug the connectors from the ECU, then measure ohms between the sensor's ground pin and the block.

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 10:11 pm
by ykill
Now that I'm thinking about it, it's grounded on the chassis....
I'll ground it on the ECU

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 10:13 pm
by mck1117
ykill wrote: ↑
Fri Apr 28, 2023 10:11 pm
Now that I'm thinking about it, it's grounded on the chassis....
I'll ground it on the ECU
Ah hah, that'll do it! Our input voltage threshold is relatively low (2 volts or something? don't remember exactly), so even a "little bit" of ground offset can trip things up.

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 10:16 pm
by ykill
Haaaaa, I should've thought about that sooner...
Can I crimp it to another already existing sensor ground or should I bring new ones?

Re: Gen 4 LS - no crank trigger

Posted: Fri Apr 28, 2023 10:22 pm
by mck1117
Shared sensors grounds are generally fine, not enough current there to cause an offset.

Re: Gen 4 LS - no crank trigger

Posted: Sun Apr 30, 2023 3:42 pm
by ykill
Ground didn't help but twisted a new wire outside the car and it worked so maybe the crimp didn't work, the noise of the ignition wires f'ed up the signal or the wire was broken.
I'll update later when I test

Re: Gen 4 LS - no crank trigger

Posted: Sun Apr 30, 2023 5:35 pm
by ykill
Well now I'm confused.
It stopped working with the wire outside the car...

Re: Gen 4 LS - no crank trigger

Posted: Sun Apr 30, 2023 9:18 pm
by ykill
I updated with today's snapshot of the firmware, it didn't work.
I forgot the key on for somewhere around half an hour.
I plugged and oscilloscope to see the signal and it was there and in tuner studio as well.
I'm not sure if it was the update that took time after rebooting or what but it's working now.
The cam sensor signal show 3 teeth instead of 1 but I can run batch for now at least

Re: Gen 4 LS - no crank trigger

Posted: Sun Apr 30, 2023 9:25 pm
by mck1117
your cam sensor is likely "bosch quick start" pattern

Re: Gen 4 LS - no crank trigger

Posted: Sun Apr 30, 2023 9:43 pm
by ykill
I'm pretty sure I changed it to a single half moon but it's been a while so I'll try it

Re: Gen 4 LS - no crank trigger

Posted: Sun Apr 30, 2023 11:31 pm
by ykill
You were right, it was bosch quick start!
Thank you!:D

Re: Gen 4 LS - no crank trigger

Posted: Sun May 14, 2023 1:04 pm
by ykill
It seems like I'm always plagued withthis setup.
Crank signal looks fine for a while
image.png
image.png (5.59 KiB) Viewed 28640 times
Then it looks like it's having a hard time getting signal
image.png
image.png (5.48 KiB) Viewed 28640 times
Then it gets worse and worse
image.png
image.png (4.83 KiB) Viewed 28640 times
I'm starting to wonder if it's the sensor taking a crap on me...

Re: Gen 4 LS - no crank trigger

Posted: Sun May 14, 2023 1:26 pm
by ykill
Signal is perfect on the oscilloscope so I would be surprised that the sensor is dying...

Re: Gen 4 LS - no crank trigger

Posted: Thu May 25, 2023 8:49 pm
by ykill
Surprise surprise, the crank sensor was the culprit, it was causing most of my issues

Little question, though.
Shouldn't the trigger show square waves instead of lines?

Re: Gen 4 LS - no crank trigger

Posted: Thu May 25, 2023 10:50 pm
by AndreyB
keyword: "lazy hall" could be relevant (or not)

Re: Gen 4 LS - no crank trigger

Posted: Thu May 25, 2023 11:05 pm
by ykill
Another issue that I had as well.
Every tunes I looked at had between 84 and 86 degrees at the trigger angle.
Mine is at 40 and it looks like one or multiple cylinder is out of phase.
I tested every coils and they do follow firing order.
Could it be possible that the coils follow the same order as the injector? (Coil 1 if cylinder 1, coil 2 is on cylinder 8, 3 on 7, 4 on 2 etc... While injectors are mixed)
My tune is here:
https://rusefi.com/online/view.php?msq=1460

Re: Gen 4 LS - no crank trigger

Posted: Thu May 25, 2023 11:11 pm
by AndreyB
What is the question? Would bench test buttons help?

Re: Gen 4 LS - no crank trigger

Posted: Thu May 25, 2023 11:21 pm
by ykill
Is there a possibility that a bug causes the coils to follow the injectors hardware configuration instead of the coil hardware configuration while cranking/running?

Everything works well in bench mode

I will re-do the pinout of the injectors this weekend to make both follow the same order to test