I can’t figure out why there’s a long synchronization delay at startup and why the injectors start delivering fuel too late, which is why the startup takes so long.
I suspect it’s an offset issue, but I don’t know how to adjust it properly…
We can help you if you Post map and log files. A picture showing injector trim percentage is not helpful at all.
v2.175 хх.emub (146.3 KB)
20260404_1429.emublog (1.6 MB)
Why is first trigger tooth 41 on a 36 tooth wheel?
because it takes two full revolutions of the crankshaft to synchronize the dprv on the rb25 .
I have a Trigger 36-2.
If we use the ecumaster logic, the second revolution falls at 41 teeth.
If you write the 5th tooth, there is no synchronization and it will not start.
There is no other way to start, if someone can tell me how to do it correctly, I would appreciate it.
yes it sees the 5 tooth in the log during the starter cranking, and as soon as it finds 41 tooth it starts…
If it doesn’t see the 41 teeth, the motor won’t start.
That logic can only be explained by the creators.
I see from a search in the community that you have been fighting this since last year.
Forgive me for thinking out loud in your thread. My friends have often told me I see things in ways they never considered. At work my colleagues have sometimes observed that this has caused me to accidentally solve a problem they couldn’t find an answer to.
So, just in case my rambling stimulates an idea for you, I’ll just think through the math a little bit here.
The EMU is looking for the missing teeth for sync to occur.
It does this by continuously calculating the difference in space (or time) between the ‘Previous 2 Teeth’, and, the difference between the ‘Previous Tooth’ and the ‘Current Tooth’ multiplied by 0.4 to find an answer greater than 10 or (>10) because it is looking for the last space that was smaller than the gap where the missing teeth are.
In the case of a 36-2, the calculation would be as follows:
Gap between previous 2 teeth = 10°
Gap between previous tooth and current tooth = 30° x 0.4 = 12 (I realise the computer is measuring time, not distance, but for the sake of keeping it simple for my pea brain 
)
This tells the EMU that the current tooth is tooth ‘0’
If I am not mistaken, the next tooth after tooth ‘0’ will always be tooth ‘1’ and the computer knows which half of the full engine cycle (720°) it is in by keeping track of the gap every time it passes the sensor.
Hope this helps.
My only question is surely there needs to be a cam sync for the initial firing of the correct cylinder, and then the computer can work with just the crankshaft after start up?
Feel free to tell me to go away if I’m not contributing any value here.
I don’t understand what you’re getting at ?
do you have a concrete suggestion on how to help me defeat the ecumaster logic ?)
I suspect it’s the offset, but I don’t understand how to configure it properly.
Ok. Concrete.
Post your scope capture along with the full log file and the project file so the Community can scrutinise your configuration and show you the way forward.
above is already there
Sorry yes it is,
I see in your log that your coils are energised at the same instant you start to crank the engine. (Battery voltage drop and coil dwell are simultaneous in your data)
About a half a second later you have full sync, first spark and injection begins.
During the next quarter of a second, full sync is being maintained on trigger tooth 5 while the engine continues to crank at about 200rpm.
Next, the computer begins to log tooth 41 as the trigger tooth and continues to crank for another quarter of a second to a total spark count of 13 or 14 before the cranking speed finally exceeds your cranking threshold of 400rpm.
The ECU State finally moves from cranking to AfterStart more than 2 seconds after you turn the key and 1 second after you have all the pieces of the puzzle together.
I think you should set your cranking threshold to 200, this will take a full second out of the delay but I still think your trigger setting are strange.
Thanks for the information, I will try it and post the result!
I was wondering what this setting will do?
In systems set up for sequential ignition with configurations that also allow wasted spark ignition, that setting will let the computer fire the engine in wasted spark before cam sync is achieved. The computer will still prioritise successfull synchronisation of the cam and crank signals and then run in full sequential mode after that. It can help reduce cranking time.
Can you put trigger tooth 5 but go to ignition coilpack settings and put ignition offset to 3 ?
Also enable injector cal, also enable prime pulse…
Then after all this:
Can you switch the cam signal to Rising and switch to higher Pullups to 4k7 and check trigger scope again, camsync tooth will change position so it might screw your previous succesful start…
Also after this there is some more for quicker start (ignition out settings)
