Sync loss at idle, during starting

[airman]

Hey all,

MS3X user here. Nissan 240SX KA24DE. Running LS2 (D585 plugs) and the 12+1 trigger wheel. Not the latest latest firmware, I will update soon.

I've had trouble starting the car. I was able to get it to finally idle on its own. See video:

http://youtu.be/kxUIr5H-Q-I

I have an MS log on my tuning laptop. I'm at work - I wasn't prepared to post this morning, but I had time. I also took a composite log when it did run. By the time I got around to looking at the graphical trigger logs I could only get them while starting. Here's an Excel during startup and then running:



I went away for the weekend and came back to it not wanting to start. So here are some trigger logs during starting:





Hopefully this post can get approves shortly. I will update with MSQ and MSL later today or tomorrow.

Cheers

[airman]

Okay.

Updated firmware, created a clean project on the 1.3.2.

Seems to start up but it's tough to idle. Sync loss is still happening consistently.

Here is a trigger log. (Double there's the duplicate long pulses there in the middle and the extra long pulse towards the end. I don't know for sure what this indicates, but I hope it helps.


Hmm, in case the edge is cut off on your screen, use this link
http://i.imgur.com/1NIZrtM.png

Attached is my MSQ.

Here's a picture of my distributor wiring (4-pin S13 dizzy)

[airman]

I tried a little more this weekend. Noticed I was set to trigger on Rising Edge, so I tried it on Falling Edge and retimed. Same issue

Opened up the MS3 unit and made sure JP1 (I think?) was on 1-2 and the other one was on 3-4. I don't remember which one was which but I followed these instructions:

http://www.msextra.com/doc/ms3/nissancas.html

The 'Inverted' it talks about - I don't have that option in my Ignition settings. I have vague memories of an option in my MSPNP2 of "Going High / Inverted" or something like that. In TS it was already set to Going High.

I have not adjusted the two trim pots, and I am having trouble getting reads on the Sync Error Logger.

[jsmcortina]

You don't have a 360 slot Nissan CAS do you? The wiring you showed certainly doesn't look like it and your settings do not reflect it. Consequently... don't use the manual page for that configuration!!!

For your 12-1 install, the tooth logger is what you should be using (don't bother with the trigger logger.) The "double pulse" in the one log you posted a screenshot of clearly indicates a problem, the engine will not run like that.

James

[airman]

No sir, I am on the 12-1 disc. What is different in the wiring while using the 12-1 disc versus the 360 slot disc? When I was on an MSPNP2 I never changed the wiring, just swapped the discs and updated the configuration.

Whoops, yep I refer to trigger logger but obviously I am looking at the tooth logger

What can introduce so much sync loss? What else can I troubleshoot and post up for perhaps more help to your guidance?

It seems like I am having trouble finding the right instructional material for setting ignition settings/wiring Nissan Distributors w/ the 12-1 disc.

Thanks!

[airman]

Something I recognized - I have the MS3 board grounded to the chassis. MS3X is grounded to the head. I will move the MS3 ground to the block/head and see if this helps the issue.

The way I see it, I am missing pulses. Noise filtering is turned off. Is that helpful information?

[edit]

After work I moved the MS3 board ground to same spot on the head as my MS3X and coils. This perhaps improved the condition slightly - it fired up and started on first try (after a few kickbacks, I mean it was able to idle right away). Still a significant amount of sync loss though.

I will attach these this evening, the screenshots are on the shop computer.

[airman]

I feel so alone with my sync loss problems :/ I'm running out of hair to tear out.

Latest logs attached.

[grom_e30]

what type of sensor is it a vr, hall ect??

[airman]

It is the stock s13 distributor. Running on the VR circuit

[grom_e30]

have you adjusted the pots its failing to see some of the teeth, in the tooth logger the longer the bar means a longer time from seeing one tooth to the next.

[Matt Cramer]

have you adjusted the pots its failing to see some of the teeth, in the tooth logger the longer the bar means a longer time from seeing one tooth to the next.

Agreed - setting the pots for more sensitivity (lower hysteresis and threshold voltage) is likely to help. It's missing pulses that should be there.

Also, personally, I find tooth logs easier to read with a 12-1 wheel than composite logs.

[airman]

Thanks Matt, I was saving the pots for last. Disassembling the ECU to get to those pots is something I haven't wanted to do, especially since every subsequent adjustment will require disassembling the ECU again. Someone should have considered that and put the pots on the other side of the board so we only have to take the assembly out of the enclosure

So I won't have to take the whole thing apart multiple times, I want to make as few adjustments as possible. I don't think I need to adjust my trigger voltage. I don't seem to be getting any extra pulses or other weirdness. My problem looks to be at the edges of my signal, and the VR conditioner page says this means not enough hysteresis.

So, that said, are we talking a quarter turn clockwise could smooth me out? Two full turns? The article doesn't really explain what to expect - what does too much hysteresis look like?

And sorry about not having trigger logs, I've only been grabbing what Phil has instructed through email support. The trigger logs still look like they have been.

[Matt Cramer]

The trigger logs are a third critter, and not particularly useful except for EDIS installs.

Unfortunately, "how much adjustment do I need?" is pretty tough to measure without checking the signal with an oscilloscope.

[airman]

Sorry. Tooth log. Not trigger log. Any time I say trigger log, let's pretend I am saying tooth log.

Understood on the amount I need to adjust - I was hoping your expertise and many hours around these you may have some judgement on what is a reasonable "first try" adjustment.

Can you please address all of the points in my post? Specifically about the part making me unsure whether this is an R52 or R56 adjustment, along with any tips or tricks to adjusting those pots without having to disassemble the entire ECU to access them?

edit
I was able to leave the boards out of the housing with the MS3X board kinda dangling out of the way so I can make adjustments to the pots and check. It has certainly helped and I'm working my way to dial it in. I have backed the R56 a full turn CCW about 1/3 turn at a time. I might need another half turn, I'm losing sync at about 3500 RPM. It was getting dark and my house is in a quiet neighborhood so I wanted to be respectful of the approaching dusk.

I will update again this afternoon/evening after I have made more adjustments but hopefully I can get it cleaned up the rest of the way.

[Matt Cramer]

Sorry. Tooth log. Not trigger log. Any time I say trigger log, let's pretend I am saying tooth log.

Understood on the amount I need to adjust - I was hoping your expertise and many hours around these you may have some judgement on what is a reasonable "first try" adjustment.

Can you please address all of the points in my post? Specifically about the part making me unsure whether this is an R52 or R56 adjustment, along with any tips or tricks to adjusting those pots without having to disassemble the entire ECU to access them?

I'm not sure, but my best guess is R56.

My usual trick for this is to undo the hex standoffs and push the MS3X into the case, then lift off the lid. This will give you access to the trim pots.

[airman]

I think we're under control. 3 full turns CCW on R56. Haven't been able to test under engine load but if I have any other problems I will update. Thanks for everyone's patience and assistance!