Cold engine startup problem

[ranz]

One problem solved, lets go on with new one now
I have somekind of problem starting up cold engine, it starts, but stalles after 1 second or less, start it again, no problems and it works. Can anyone suggest what to change and try it get work with first cranking.
Here is log file from that: http://ranz.planet.ee/startup.vemslog

Cranking on from 2,5 seconds, it always needs to crank something like 1,5 seconds (the RPM at dash goes up to 7000 and back to 0, then it starts, also with warm engine). At 4 second it starts and at 5 second it stalls.
New cranking at -21.-500 and it starts a -20.-125 (I think it has minus on them because I had to unpower the ecu to get the car cranking again) and the RPM goes up and everything is OK.

[rob@vems.co.uk]

I can't read the VEMSLog here at work - but what do the dials do just before it stalls?  Check the Injector PW readings from start to fail.

[ranz]

I can't read the VEMSLog here at work - but what do the dials do just before it stalls?

I can´t see that any of the dials makes something wrong...

Check the Injector PW readings from start to fail.

PW reading is basically the same with the second start when the car starts fine.

[rob@vems.co.uk]

The dials will indicate that something is wrong - I expect to see the PW drop rapidly just before the engine stalls.

The second start will be into a cylinder that has recently had combustion, so there will be better fuel evaporation

[th.b.w.]

increase the afterstart enrichment at this point to +10%

when it is not right, decreas it -10% and see...

Thomas

[ranz]

increase the afterstart enrichment at this point to +10%

when it is not right, decreas it -10% and see...

Thomas

Tryed it already, did not help. But now I noticed thad @ cold cranking the IAC duty is 70Hz and thats a little too much. Now I lowered cold cranking duty to 30 and hot to 50 and when starting the car, it was @38Hz and the car started really well I´ll test it tommorrow again to be shore that it was the problem.
Log: http://ranz.planet.ee/startup2.vemslog

But now another thing what I noticed.
I turned the key @ 1.750, but the cranking lights up @ 2.78, so for a second there is nothing happening... and the car starts @ 4. second. What could be the problem? why takes it so many time and does not start with a second or something...

[mattias]

You mean dutycycle % and not frequency = Hz.

Your cranking rpm is just above 100 rpm, that is not a lot and might explain why the rpm reading appears a second after the engine starts turning. The VR signal can be quite weak at such low rpm, it could be the reason why. Nothing will happen as far as ignition or injection until there is a rpm signal and the ECU has synchronized to it, in your case with the cam signal as well.

You should set your secondary max trigger angle to 359 so you won't get as many false "too many sec trig" in the log.

With 15/2 for decrease/increase integral limit you're practially railing the integral all the time. I'm not so sure the PID values are doing anything to regulate idle, it's basically all fixed by the idle ref duty table. Anybody else have a different idea?

[ranz]

You mean dutycycle % and not frequency = Hz.

Of course, I don´t know I added Hz to them

Your cranking rpm is just above 100 rpm, that is not a lot and might explain why the rpm reading appears a second after the engine starts turning. The VR signal can be quite weak at such low rpm, it could be the reason why. Nothing will happen as far as ignition or injection until there is a rpm signal and the ECU has synchronized to it, in your case with the cam signal as well.

I can not test it right now, but if i remember right, with 1.1.74 it started better...

You should set your secondary max trigger angle to 359 so you won't get as many false "too many sec trig" in the log.

Changed it... still same triger error sometimes. It appears only with cold engine, with warm one, I have not noticed it.

With 15/2 for decrease/increase integral limit you're practially railing the integral all the time. I'm not so sure the PID values are doing anything to regulate idle, it's basically all fixed by the idle ref duty table. Anybody else have a different idea?

The integrals I got from forum somwhere, they where 50/50 before and somebody suggested to lower them to 15/2. Tested both of them today, no cange???
And the PID values are doing something to regulate idle, because I played with them today a lot of time, and idle changes if I change the values.

And now back to the original topic issue. Yes the problem was @ my cranking IAC values. The car today started and did not stall anymore Yes it was not perfect start, but almoust, so I added some fuel to cranking and afterstart enrichment to.