Having an issue starting my car. Trigger is achieving sync but its not injecting fuel right away?? Then just as the injection starts to happen Then the primary trigger loses counts as the secondary trigger changes state and loses all sync until the next cycle??? Car can eventually start after further cranking if it has enough fuel before it losses the primary trigger counts again. I am tearing my hair out trying to understand this. Once syc happens and ignition counts start to happen shouldnt injection happen straight away?? no issues with triggers once engine starts but why is lossing primary trigger as secondary trigger changes?
Can you post the whole log file and calibration?
What engine and whats the cam trigger wheel look like?
I don’t think you need the synch to wait until the CAM is decoded but I want more information before speculating
Its a jaguar 4.2 xk xj6 from 1982. Cam trigger is a cherry hall sensor reading one tooth pin i fixed to cam sprocket. Crank sensor is a 36 tooth minus 1 with a hall sensor. Are you saying the option on the secondary trigger for sync as soon as cam is decoded should be disabled?
20260126_2100.emublog (57.0 KB)
jaguar2.emub (145.7 KB)
yes, choose disabled.
You log is showing multiple trigger errors, so that’s why its not sparking.
I’d also check the scope log when cranking to make sure that the teeth aren’t lined up. You don’t want the cam and crank teeth to line up on top of each other.
I figured out The trigger errors are something to do with the 36-1 trigger wheel. Its when the missing tooth passes the sensor i get the trigger error and the rpm drops to zero. Why? I dont get trigger errors once engine starts. What i dont understand is it does acheive sync for a 1 or 2 seconds and executed sparks are counting so why doesnt it start injecting fuel even for those seconds until it looses sync again? The enable sync without cam sync setting. What setting allows it to crank on wasted spark? Thats why i had it set to sync as soon as cam is decoded. If i disable that setting what does it mean? It should be easier to start on wasted spark no??
There is a separate ignition output parameters called “Ignition out cranking” where you can assign waste spark until cam sync is achieved. It does require a crank trigger with a home, like a 36-1 or 60-2 etc.
Don’t let the wording in the help file trip you up, the enable button needs to be checked for this to work; it’s not talking about the trigger settings even though the language is similar.
Have you done a trigger scope?
I’m not privy to exactly how they’ve written the code but the engine position has to be understood by the ECU before any ignition or injection event occurs, and that requires at least one or two revolutions past the missing tooth.
It can do a prime pulse which injects fuel when it sees any engine movement (might actually be a combo of that and the dip in battery voltage, again not privy to the code). You have this enabled ad around 4.1 ms at the temperature you were attempting the start in. That’s a way of introducing fuel in faster then waiting for sync, ideally it’s ready to start as soon as sync is achieved.
In your log though it doesn’t look like sync is stable even though it’s being achieved. I’d be looking at a scope log to make sure all 35 teeth are being picked up as well as the missing tooth section and that there’s no overlap between crank teeth and cam teeth events. this can present this way where it will report sync but also an error.
The error’s I am seeing are for an unexpected missing tooth. This can be tooth overlap, air gap or EMI etc.
I have done the scope and there doesnt appear to be any missing teeth. 35 teeth between the gaps its reading. Yes its possible the low battery voltage is an issue. the enable sync. without cam sync setting below. I dont understand this setting. What exactly do each of the options do?
Please, Can someone from ECU master comment on why my rpm is dropping to zero during cranking, its stopping sync and i cannot figure out why. Please help!