1995 Mustang GT Megasquirt Timing and ignition settings question

Nov 23, 2019
26
6
13
Ohio
I was able to get my car started and it idles (somewhat) meaning I can hold a decent AFR without my foot on the throttle, this will require some more fine tuning. OK, so I my main question has to do with getting my timing set correctly. I restabbed my distributor at 0 degrees. I confirmed with a bore scope because my balancer had several sets of marks. Car fired up and I let it get to temp and began to tune the idle. I went out with the timing light to align the marks with my balancer. Marks were oscillating all over the place. I remember that when I set the timing before the Megasquirt upgrade I pulled the SPOUT. Well the car will not run with the SPOUT out. I watched a video from a member and he says I do not need to pull the spout to set the timing. Fair enough. I contacted the guy who sold me the ECM and he told me that the last car he did that did not run with the SPOUT out he had to rewire the car because it had the incorrect wiring harness. That doesnt seem to be accurate to me. Here is what I found because Fox cars are not the same as the 94-95 cars. https://www.corral.net/threads/timing-way-too-advanced.1411496/page-2 I set the settings to his, but I could not find all of them like (acceleration compensation and maximum dwell.) Where are they in tuner studio?? Anyways I am just wanting to know how I can get my timing from oscillating. Can anyone assist me with this and make sure I have the correct ignition settings?
 
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ignition settings> ignition options / wheel decoder > [top right of the page] set fixed advance to fixed the set the fixed timing value below.

fox cars with the grey TFI, set dwell type to standard duty at 50%. the ecu cannot control the dwell because the TFI does that internally.
For the Black TFI on the later cars nominal dwell 3ms and spark duration 1ms.

you would do well to go onto msextra and read the manuals. or use the tool tips in the software.
 
ignition settings> ignition options / wheel decoder > [top right of the page] set fixed advance to fixed the set the fixed timing value below.

fox cars with the grey TFI, set dwell type to standard duty at 50%. the ecu cannot control the dwell because the TFI does that internally.
For the Black TFI on the later cars nominal dwell 3ms and spark duration 1ms.

you would do well to go onto msextra and read the manuals. or use the tool tips in the software.
to be honest, I didn't even know there was a manual like that besides the one that came in the box with my Megasquirt ECM. So thank you for the tip which I will pass on to others.
 
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After trying those settings and reading that section of the manual, am I missing anything else as far setting base timing? Timing jumps all the way from 0 degrees past 20 degrees when looking at it with a timing light. Still no spark with spout unplugged.
 
You wont get any spark with the spout unplugged. You lock the timing in TS and set the offset to 10*
Then adjust the distributor until you get you locked timing value
Good grief! You mean all of the years I spent learning to troubleshoot these systems and timing these engines is worth nothing now. Let me run the steps by you on what I should do.

1. Under ignition settings - Timing for fixed or advanced for degrees set at 20.
2. Under ignition settings - Trigger angle/off set degrees - set at 10
3. Under hood at distributor - adjust the distributor until I am at 20 degrees and tighten the bolt. Then I will be good to go and the marks wont fluctuate?

Does all of this look correct??

1589748336433.png
 
If this is a microsquirt, the output needs to be set going low. Going high will give an erratic timing value in this application
It’s a MSPNP2. So the let me make sure I understand their lingo here. You’re a controls guy so you’ll understand this. So there are certain instances where we program outputs to “fire” on a negative edge triggered pulse (I program with Mitsubishi PLCs), is the “falling edge” they are referring to the same here?
 
There is alot wrong if that is a ms2pnp.

Why is the cam input set to map? Why is the ign output set on wled? I can understand if you are firing an msd box directly but if you are trying to use the standard ms2pnp harness output it needs to be set to ign out.
It seems to me you have either started with an incorrect tune file, gotten some misinformation, or interpreted information incorrectly.

Post the tune file please

Yes rising or falling edge of an input, the negative side of a ac wave in this case.
 
There is alot wrong if that is a ms2pnp.

Why is the cam input set to map? Why is the ign output set on wled? I can understand if you are firing an msd box directly but if you are trying to use the standard ms2pnp harness output it needs to be set to ign out.
It seems to me you have either started with an incorrect tune file, gotten some misinformation, or interpreted information incorrectly.

Post the tune file please

Yes rising or falling edge of an input, the negative side of a ac wave in this case.
Awesome thank you for the clarification. The cam input and the WLED setting I was told was what was needed since this a 1995 car and not a Fox setup for the Megasquirt MSPNP. I will post the tune file once I get home. Let me know the changes you make and why if you would please. I am never going to understand and learn if someone just does it for me. Thank you in advance.
 
Let me know that you think, and let me know what I did wrong so I learn from my mistakes and my lack of knowledge. Thanks
 

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Just like I thought, WLED is the ign output for a microsquirt pnp NOT the MS2pnp unless you are triggering a MSD box directly. using the factory harness the ign output needs to be set to IGN1 and going High.

Also you will want to set the incorporate AFR before you begin any major tuning.
 
Just like I thought, WLED is the ign output for a microsquirt pnp NOT the MS2pnp unless you are triggering a MSD box directly. using the factory harness the ign output needs to be set to IGN1 and going High.

Also you will want to set the incorporate AFR before you begin any major tuning.
Awesome!! Thank you for the clarification on this. No MSD box, just the factory setup. I will go back and set the ignition settings on this when I get home.
But can you see anything that I have setup that would cause my timing to not stay fixed?? When trying to dial the timing in it keeps moving around. With the factory ECM I just pulled the SPOUT, set the timing then plugged the SPOUT back in then let the TFI module take over. But I’ve been told by you and DIY auto tune that you don’t remove the SPOUT.
 
Wow, incredible timing on this thread<pun intended>. I am struggling with a MSPnPGen2 as well. Glad to see I am not the only one with Spout out no run, I had folks on a MS group saying to pull it to set timing and was scratching my head as doing that I had no spark.

I have a 393W build going into my 94GT and I have not been able to get it to fire just yet, but reading about the fixed timing above I will try that.
 
You can do it either way. SPOUT out is more familiar for people and faster too. You either set base timing just like you do with a factory ECU with SPOUT out and just tell Megasquirt what the trigger angle/offset is (because trigger angle = base timing) then put the SPOUT back in and you're done. Or you leave SPOUT in, set fixed timing, and play with the trigger wizard until commanded timing = measured timing, then you need to go back and set use table again. It will probably take you longer to get there playing with the trigger wizard, but at the end of the day it doesn't matter which technique you use, they both lead to the same place.