O wow….I did not catch that ……so it is the intention. Thank you!!
Hi!
Now you can correct boost target. So if you set your boost target fixed to 300 kpa then you can make 150kPa if you enter -50%, 100kpa if you enter -66% and so on.
For next releases I add separate boost target table in timers section. That will be easier to manage.
Perfect!!!….Thank you!
After updating to 3.059 firmware from 53, interpolated fuel cut rev limiter is not working. After discovering this I switched to per cylinder fuel cut and that works as intended.
Before
After (Same settings - fuel cut type)
There is change in the strategy to make it simple and more smooth without possibility of overshooting.
So on your 2nd log the rev limiter is working (as the rpm do not cross 8500). But due to the operation principle it doesnt work directly on fuel cut %, so the fuel cut % channel is still 0.
Maybe it is good idea to put some values there if there is cut during rev limiter.
I can’t hear it doing any cut events until a hard cut at the limit target, nor does it show on the dyno graph as if it is cutting.
if you see here the over run in the ignition is active and its executing spark counts.
attched is the log.
(i add > so just to be clear, that intermittently . will driving it will just start to do spark cut >from overrun dos not always happen . but the over run function is not active .)
27203301.BG3 (1.2 MB)
Can you publish the log ?
I’ve tested the soft rev limiter based on fuel cut and works as it should.
Yes it is a bug. The spark cut is active when there is no Exit ingition ramp state on exit. I will build 3.060 version just with this issue fixed for Monday.
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thanks for this fix . its already costed me time to strip a completely fine engine and found nothing wrong .
Hello @Jadzwin_ECUMASTER
Just wondering if you have looked at this situation on overrun when DBW Target is from Idle despite idle control not being active due to map reading?
Is this correct?
Its probably taking the position from the „armed state airflow“ table, depending on your ramp down offset rpm
Here is the log and project file. Note that I lowered the rev limit target to 5500 for testing purposes, and did this at low load with slowly climbing RPM. It is definitely just bouncing, no partial cut happening here. Per cylinder fuel cut works perfectly.
Rev Limiter Malfunctioning.emub3 (70.6 KB)
Rev Limiter Malfunctioning.emublog3 (27.6 KB)
@Jadzwin_ECUMASTER did you have a chance to look at this?
Yes, all works ok. The problem is that after cutting fuel, there still is residual fuel in the intake what can cause some oscilation. If you change it for the spark the cut should be much faster and RPM line should be flat.
The only solution is to cut fuel and spark for given cylinder at the same time, but still it will be much slower than spark based rev limiter.
Other option is per injector fuel cut as you use it.
The help file for Cranking gap detection scale contains the following:
isGap = T * 2 > previous T
This means the ECU considers a gap (missing teeth) if the current T is at least twice the previous T.However, during cranking, especially in high-compression engines, the crankshaft’s angular velocity can fluctuate, affecting these time intervals. The Cranking Gap Detection Scale modifies the gap detection formula to account for these fluctuations:
isGap = T * 2 * cranking gap detection scale > previous T
Shouldn’t the formulas be:
isGap = T > 2 * previous T
and
isGap = T > 2 * cranking gap detection scale * previous T
While we’re on the subject, what would be a good value for Cranking gap detection scale for a high compression engine. It cranked reliably in warm weather, but now cranking it with cold oil causes the VR trigger signal to vary (frequency and voltage) and it is failing to sync. This scope is with the trigger disconnected from the ECU. Also, how should the trigger Adaptive threshold be set to compensate for the varying voltage?
Hello!
You are right. isGap equation is wrong. It will be corrected for the next build.
The varying amplitude at cranking shouldnt be a problem. Could you please post a scope file from non start crankin ?
Also there is an option for high compression cams to create window where the gap could be detected (enable CAM sync tooth window).
If you publish the scope I will be able to advice.
Here’s the external oscilloscope connected to the trigger”
and the EMU internal scope:
These are from the same starting attempt.
i think you have the wrong edge selected