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Another ref/sync classic, it wont start!

Posted:
Sun May 04, 2025 6:09 am
by Islandworks
I've been fighting with my Motec M150 ECU during the day to get it started for the first time. I've done the followng so far:
-Checked so all spark plugs and injectors are going to the right cylinder
-Checked for spark and for fuel from injectors
-I now wanted to set the engine to "wasted spark" so I can eliminate any issues with incorrect reference from the hall sensor on the cam shaft.
I however cannot find the setting in the Mtune 1.5. Attaching the tune I've used which is what I got from my friends 964 and something I wanted to use as a base map before I do a dyno.
Can anyone help me explain where the setting went?
Porsche 964
Drive by wire
Coil on plug
Motec M150
LTCD
Re: Another ref/sync classic, it wont start!

Posted:
Sun May 04, 2025 12:15 pm
by David Ferguson
First, does Engine Speed Reference State achieve Cycle Lock? There will be no fuel or ignition events until this happens. Normally, the next step would be to use Online->Capture inputs, to look at the Engine Speed Reference Signal, and the Engine Synchronisation Signal (whatever Udig was selected for the Engine Synchronisation Resource).
You can save that file, and export it, then upload it here we can see if you what you are measuring matching your configured package
There is no reason to try wasted spark, if you are worried you have the crank reference offset on the wrong phase, just add 360 (if the current value is less than 360), or subtract 360.
One of those should work if the offset is correct. Have you been able to use a timing light to verify the offset is correct?
Re: Another ref/sync classic, it wont start!

Posted:
Sun May 04, 2025 7:10 pm
by Islandworks
This is what I got from the sync capture. It looks normal to me?
Re: Another ref/sync classic, it wont start!

Posted:
Mon May 05, 2025 1:11 am
by Clean RC
Hello.
I just looked into the firing order side of things. I am wondering why you have them assigned the way you do. IE 964 firing order is 1-6-2-4-3-5, and it looks like you have the injectors and coils set up differently as well.. I would go back and look in this area first. I am no expert on flat 6's but my straight six is set up in order 1 2 3 4 5 6 ect.. and the Motec determines the firing order in set up.. I hope this helps.
Re: Another ref/sync classic, it wont start!

Posted:
Mon May 05, 2025 4:03 am
by David Ferguson
I suspect you are having trouble getting to Pattern Lock, because the "Engine Speed Pin Active Edge" needs to be Rising based on your Input Capture. Or you could reverse the wires going the crank sensor to change the polarity.
In your input capture, you can see that it thinks only 348 degrees (instead of 360) between missing teeth, or 696 deg between sync signals (should be 720). This may change your Engine Speed Reference Offset by 3 degrees, so verify the timing after this change.
Your cylinder TDC values (ie, firing order) match what I have for a 964-based engine.
Also DBW settings

Posted:
Mon May 05, 2025 4:14 am
by David Ferguson
Unless you have run this exact throttle setup on a similar engine with the "Idle Actuator Throttle Aim Maximum" set to the current value of 3%.
I would suggest this will want to be higher 5%+ for ITBs, and probably 10% for a single throttle body. Too low would lead to hard to crank / start.
Re: Another ref/sync classic, it wont start!

Posted:
Mon May 05, 2025 5:17 am
by Islandworks
Thanks for all the support so far!
I changed the rising/falling edge on the sensor and bang it started.
I’m trying to get my old sync-light to work with my CoP setup to verify that it’s correct. I took another coil attached a wire to it and connected it to a sparkplug I clamped to the chassi. The spark plug is giving spark all right but cannot get the light to register it despite checking power and direction of the clamp.
I’ll dig further a bit!
Thanks for the tip on the idle!
Re: Another ref/sync classic, it wont start!

Posted:
Mon May 05, 2025 11:25 am
by David Ferguson
I use this for connecting a timing light to COP ignitions:
https://autonerdz.com/product/ta037/Even with this, I often find that many lights won't work at cranking speeds and need the engine to be running / idling to start flashing.
Re: Another ref/sync classic, it wont start!

Posted:
Thu May 08, 2025 7:07 am
by Islandworks
Still working away on this one learning the Mtune 1.5...
I've now validated the timing, the compression and got it started once. I've also checked my map against a very similar built engine with the same Motec setup.
My engine is flooding during cranking and I cannot seem to understand why this is. I did notice that I had the regulator reference set to ambient rather than manifold (I have a hose to the regulator) but have not been able to check if that resolved the issue.
One thing I notice is that my Lambda is readying 2.55 during cranking but I have no canbus error messages. Is this normal?
Any tips on how to proceed avoiding the flooding?
I checked during cranking and my injector timing is like 30ms...
Re: Another ref/sync classic, it wont start!

Posted:
Thu May 08, 2025 9:58 am
by Stephen Dean
Normally flooding on cranking is related to the Engine Crank Fuel Volume Compensation table, but yours looks pretty normal. I would check that you have valid data for all of the sensors, i.e., the Manifold Pressure is not reading 200kPa at engine off.
This is one time where going back to Tune 1.4 can help, in that there is a Complete Fuel Calculations Worksheet in the Monitor workbook, this will show you all of the calculations and data used to calculate the Fuel Volume injected and you can see if there is a value that isn't correct quite quickly.