Upgrade from 1.1.27 to 1.1.8x Galloping Idle

[tweak]

Finally i could upgrade to latest version, primary because i wanted better idle and acc enrichment features.
But the idle actually got worse, the PID settings etc. is the same as before, and the idle was OK with the only exeption that it would sometimes stall at higher MAT's. Now it's having difficulties to settle and jumps between 700-1500. Does not sound very proffesional nor easy to drive slow.
Also i noticed some of the same effect in the very low load areas, when the IAC is not working.
I see the partial fuelcut is set to some values, which i don't understand. Can this have an effect?

Also i noticed that the lambda table went from 12x12 to 8x8. Normal?

Will upload a log but not until tomorrow.

[tweak]

And here is the log, but it may require some zooming in to find the problematic area.
http://nortrack.no/annet/new_firmware.vemslog

[GintsK]

First disable partial fuel cut by changing fuel cut/resume values (hit F1)
Retune fuel resume to rpm not Kpa. Or go to really low KPa like 18kpa.
Then try to retune idle PID alittle. May be lower P to 10...20, and rise I to 15...25 together with narrower I limits 20...40.
Lower TPS idle treshold to 1% and MAT slope for IAC to 3..4%

Integral minmap seems to high. Try somewhat like 32Kpa.

after, if all seems more stable you can switch on ignition advance aid for idle. And enjoy result.

Of course fueling should be tuned fine.  Now you have lambda fluctuations at idle.

[tweak]

Ok, so rpm fuelcut - rpm fuelresume = has to be something different from 1100 as i understand.
What should i set the partial fuelcut values to then? What is this for anyway?

I did not have lambda fluctuations at idle before - thats something that came with the new firmware. I did actually try to play with the VE values to increase the idle fuel, but it did not make much difference. The lambda table changed itself to 8X8, this might possible have an influence as well.

I'll try to play a bit more and get some more logging done.
Also it would be helpful to know what values is sensible for MAT / refpos table for the IAC.
thanks

[GintsK]

Yes 1100 and 1000 IIRC. It is for driving with pre-opened throttle when using antilag setup.
You can use somewhat like 2000 fuelcut and 1800 resume and 0kpa. It will solve problem when rpm drops below idle rpm after throttle release.
8x8 table probably  is not the reason. But you can try to flatten it at idle.
Try to tweak VE table at idle area. But may be reason is injector dead time configuration. See: http://www.injectordynamics.com/dynamic-characterization.html

Do you means CLT/refpos? Little higher than at desired idle rpms.

[tweak]

I tried to put RPM fuelcut and resume at 2000 rpm and it helped a lot. Idle now better than it ever was with previous firmware of VEMS.
But i actually increased the fuelcut to 32 kpa as i like to have a bit of engine break. Also works well so far. Resumes at 1200 rpm, but probably what makes it possible, is the new feature for maxmap for Integral which i set to 40 kpa. Before it would wind up a huge integral when engine braking which it had to recover from in 0,5 sek when clutch was pressed. I find the RPM fuelcut is much harder than the pressure based, not very good for smooth driving.

Now there is so much else to figure out like the injector trim, but first i want the specs for the injectors right.

Many thanks Glintsk

[tweak]

And here's another log for a cold start.
Idle is OK now but still a few issues there:
http://nortrack.no/annet/coldstart.vemslog

The Acceleration enrichment is on all the time for cold engine, leading to a pig rich startup.
The knock retard is always on, (i better disable it probably???)
The table for injector angle is impossible to set correct, the top value always reverts to a silly value after trying to burn to ECU. Looks like a bug.

Another thing is that i noticed higher EGT's than before upgrade, but it's not visible in the log.