I was trying to move my Primary trigger edge from Falling to Rising to avoid some Primary Unexpected missing teeth error since the Secondary and primary signals were overlaping at some point.
I got very confused when I tried many setups and couldn’t get the primary trigger to read when set on Rising edge.
Did anyone encounter such cases on EMU Pro?
Engine is a K24 with stock trigger system (wheel 12+1 and sensors).
In the end I moved the secondary trigger to Rising edge and it solved the overlap issue for now, but its still close and I’m not comfortable with that. The ideal scenario would be to have the primary read on rising edge and secondary on falling edge.
Falling edge on Crank “speed” trigger is what you want to use in most cases. Its a cleaner, faster more defined edge. Rising is fine for sync.
From the looks of your scope log I would use Longer than factor for sync and set it around 3.2-3.4. This would then use the tooth in the picture that shows a factor of 3.6 and move you closer to the middle for sync. No worrying about trigger edges being close at that point. Rising edge would put you around tooth 4.
I tried to rev the engine and I’ve got Unexpected missing tooth errors inthe log as well as kind of rev limiter or engine breaking starting with 5800 rpm.
I tried old settings with N+1 and new settings with Longer than factor
Both gave similar result, maybe LF sometimes less and sometimes same.
I tried and got the scope in that moment + log. Would apreciate if someone can point into the right direction.
I noticed as well a lot of noise in the VVT intake cam reading even though I applied maximum filter. Not sure if it can relate to the sync issue or not, or maybe the Primary trigger Start tooth for VVT .
You need to solve the noise problems on both primary and secondary triggers. This is the reason of wrong position detection.
You can see spikes in scope on secondary trigger and intake1 for N+1 settings. Also, in both log files there are problems at higher RPM, see channels Primary Unexpected missing teeth and Secondary Rejected spikes.
How did you connect the ground of trigger sensors? Is it connected to Digital GND?
I changed the cam sensors triggers to digital gnd insead of sensor gnd how those were wired and tried it, and the result really amazed me, no issues at all. Reved 7k RPM for now.
I’ve been thinking about it recently. Although the grounds are internally connected, they are not just a common layer on the PCB. I knew the signals from digital sensors may affect the analog signals, but this surprised me as well.
The distinction between the grounds is there to create distinct current paths.
One for switching currents (digital), one for continuous currents (analog), and one for power currents (supply and outputs).
Having sensor and load currents flowing through the same piece of conductor makes it so that the voltage drop due to the load current is read as a change in the sensor signal. Switching high-current loads in that scenario will significantly affect the sensor reading.
Having different types of sensors connected to the same ground shouldn’t have a significant impact, since there are no large current changes. A switching signal can add a small amount of noise to the analog reading, but the reverse is very unusual, because a small amount of voltage noise shouldn’t affect the reading of the digital signal.
You might want to check whether you don’t have any analog-to-power ground loops through the harness. To do that, you should disconnect all connectors from the ECU and check continuity between the power and analog ground pins in the ECU connectors on the harness. There should be no connection between them. If there is a connection, you have to find it and remove it.
