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Need MS2 Start Up Help


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I just installed MS2 V3.57, LS2 COP's and Modified Turbo ZX dizzy with Maxima CAS installed. I put all this in my 1976 280Z 2+2 NA. I was at the suppliers shop and witnessed the qual test for the ECU, Harness, and Base Tune. As of now, unknown variables are the coil packs, and CAS. I'm fairly certain my install is perfect and have gone over all the wiring several times. The engine ran perfect before I yanked out the factory EFI system. The problem is, I am not getting any spark at the coils to set off the strobe in my timing light. I even returned the first light thinking it was bad out of the box. Hence, I can't set my base timing and move forward. Question- is the Megasquirt setup program causing this ? With so many different setups out there, I don't know exactly what I should have in the Ignition settings for my setup. Can someone please share how the Ignition settings should be set for this and what testing (voltage's etc) at the coils and dizzy I can do to show they are good ? I'm dead in the water for now ..... Thanks in advance.

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1 hour ago, Screwdriver said:

As of now, unknown variables are the coil packs, and CAS.

 

I'd try to know more about these unknowns.  You can waste a lot of time otherwise. 

 

You said that you have LS2 COP so there are no coil packs.  There are two reasons a coil won't discharge - no power or no making and breaking the power circuit.  You can probably check for power with a meter at a coil.

 

The CAS can usually be tested also.  Here's a typical video, it's actually pretty good.  I don't see any reference to checks with a meter in your post.  That's the place to start.  

 

Or, if I recall correctly, Megasquirt itself will confirm some of these things.  Doesn't your "dashboard" show the CAS signal?  Kind of looks like you just plugged things in and turned the key.

 

https://www.youtube.com/watch?v=RvuzZJqQDf4

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Thank you. Yes, we ran the CPU and harness on the suppliers test engine and was provided the base tune. I was led to believe that I had to install it, set the base timing and crank it up then, start the tuning fun. At this point, I can't even get base timing set to move forward. My bad on the terminology. They are the GM LS2 coils mounted on a bracket in a Coil Over Plug configuration with a short plug wire. L28 NA engine. I do have a good volt meter and test light. I just don't know where to check and for what value. The GM coils have 4 wires and the Delphi style plug. The Maxima CAS has 3 wires. Which wires do I check and for what values? Also, if the Megasquirt Ignition setting are not set right, will that cause this to happen? If so, tell me what values to put in the boxes to make this work. I have to know I have everything right on my part before I take the coils or Dizzy CAS back to the supplier and say they don't work.

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Sorry, but you're going to have to dig in a little deeper.  You didn't watch the video I linked, it shows how the three wire CAS works,  You didn't answer the implied question about the Megasquirt software and whether or not it shows the CAS signal.  Do you have Tunerstudio, or other tuning software?

 

There's a bunch on the site about CAS signal problems.  Since it worked at the supplier's shop the problem would seem to be with your equipment.  The CAS signal is most likely.

 

 

Here's one that covers a few things.

 

 

https://www.diyautotune.com/support/downloads/

 

http://www.tunerstudio.com/index.php/tuner-studio/tunerstudioms-menu

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Ok, I did watch the CAS video and did the tests. With the 3 wires, I have 12v, Gnd, and 0-5v signal. For now, it appears to be working properly. And, you are correct that the ignition advance is showing as one of the MS gauges and shows 12 deg while cranking. So that looks correct. I think I found the culprit at the coils. The switched 12V (key on or cranking) is not there. So, let the fishing trip begin. Any advice on where to start or how to tackle this? Thanks so much for helping.

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Coil power typically comes through a fused switched circuit.  The Megasquirt system grounds the circuit to control the spark but the power to the coils can come from anywhere.

 

You might browse some of the wiring diagrams on the DIYAutotune site or see what you can find on Hybridz to see how people power their COP systems.  I haven't used one so don't know if there is central point from which the coil leads split or if each one has its own circuit.  Follow your COP wires back and see what's missing.

 

I did a Google and found a few things.  The first one uses the same words I did, so I might be on to something.  There's probably a wire from your harness that you need to connect to switched power.

 

http://www.megamanual.com/seq/coils.htm

 

 

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I read this very powerful statement in the MSExtra documention : The tach input is one of the most important signals going into the Megasquirt and correct system operation is not possible until the tach input is correctly installed and configured. Until the Megasquirt reads the correct rpm, nothing else will work.  Where is MS getting the tach signal from? 280ZX optical Dizzy and using LS2 COP.  I'm still not getting anything at the coils during cranking. Maybe this is the culprit ?

Edited by Screwdriver
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Tach input is the CAS signal.  Tachometer is just a meter that measures engine speed, which is what the CAS does.

 

You didn't confirm power to the coils yet.  You have to have power to the coils.  Power AT the coils is not provided by the Megasquirt system.  Megasquirt provides and controls the grounding of the power.

 

Look down at the bottom of this picture where I scribbled.

 

https://www.msextra.com/doc/general/ms2external.html

 

image.png.51bba7252f95250d52a1264ae85ab8f3.png

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Excellent diagram! Thank you. I was able to talk to the supplier shop today. My 280Z is an automatic transmission. Most of his installs are manual tranny's. He suggested that the neutral starter switch (or Inhibitor switch as the FSM calls it) may be interfering with my voltages. And that I may need to join some wires together like I did at the ballast resistor to complete the circuits. Do you have anything you can share along this path ?

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CZCC.com has wiring diagrams and FSM's  The FSM chapters typically have a smaller diagram specific to each area.  I'd look through those.  https://www.classiczcars.com/files/

 

Of course, you can also examine the wires at your shift linkage and the switches on your transmission.

 

Here's a site I like to use to see which parts go where.  Look under Powertrain and/or Electrical.

 

http://www.carpartsmanual.com/datsun/Z-1969-1978

 

 

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On 5/16/2020 at 11:22 AM, Screwdriver said:

Thank you. Yes, we ran the CPU and harness on the suppliers test engine and was provided the base tune. I was led to believe that I had to install it, set the base timing and crank it up then, start the tuning fun. At this point, I can't even get base timing set to move forward. My bad on the terminology. They are the GM LS2 coils mounted on a bracket in a Coil Over Plug configuration with a short plug wire. L28 NA engine. I do have a good volt meter and test light. I just don't know where to check and for what value. The GM coils have 4 wires and the Delphi style plug. The Maxima CAS has 3 wires. Which wires do I check and for what values? Also, if the Megasquirt Ignition setting are not set right, will that cause this to happen? If so, tell me what values to put in the boxes to make this work. I have to know I have everything right on my part before I take the coils or Dizzy CAS back to the supplier and say they don't work.

 

Did the supplier tell you exactly how to connect the new harness to your existing harness(es) wiring? Megasquirt in an S30 is never "Plug and Play". 

 

The wiring to the GM coils and/or number of wires used has nothing to do with the CAS wiring. The CAS supplies a "tach" input to the ECU - it just supplies the ECU with the engine speed. BUT, until the ECU "knows" the engine is indeed turning, it can't do anything - so the CAS input is critical. This signal is displayed in you tuner studio gauges EVEN IF the engine is not running. When the engine is cranking, IF the turner studio gauge RPM is showing engine rotation, THEN it IS receiving the CAS signal or "tach input". That's where that virtual gauge gets it's information - from the CAS.

 

The GM coils do need power at ignition on. Normally it's supplied through an EFI relay. Using Tuner Studio, you can test each coil for proper operation (and sequence) BEFORE you start the engine. It's part of the recommended start-up procedure which is in the "Setting Up" manual. I understand that you've already seen this setup work on the demo engine - but, that was on the demo engine not yours... I'm more interested in HOW you connected the supplied harness to your 280Z.

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I totally agree! And further more, I'd have to say that all S30's ARE NOT wired the same. So, there is no instruction manual that can be written to make it fit everyone's car. After not sleeping for about a week constantly thinking about this, I finally fired it up last night. I can report that Megasquirt is extremely sensitive to ground points. I moved from chassis ground to engine ground and it liked that. I was even thinking of adding another ground wire from the battery to the engine. It runs like a dream now. I think I added a bunch of horsepower with this mod. And no more smoke out the tailpipe. Now two questions. My dash tachometer isn't working at all. I plugged the MS tach out into the blue wire at the old coil location that I think drove the tach. Didn't work. Any ideas ? Also, what is the sequence to "Burn" a change in Tuner Studio ? After setting my timing with the engine running, I hit "Burn" and it killed the engine. Wasn't expecting that. Also, what is my next move now? Do I need to go back thru Tuner Studio and calibrate all my sensors or, just start driving it and get auto tune to do its thing first?

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