0 RPM with engine running

[MIkedaf]

I seem to be having a strange issue where the rpm in the logging data goes to 0 for less than a second and this causes the idle control to switch off despite the engine not cutting out. Can anybody shed some light on what might be going on here as I have checked and cant seem to find the cause?

Looking at the log I can see the idle control status immediately before is at Hold-Throttle open status then goes inactive as RPM = 0, this is all whilst the throttle is still open.

I have also checked triggers 1 and 2 status and the arming voltage looks fine and trigger signal listed as yes for both.

any help appreciated as it driving me crazy.

Thanks

Mike

[Vaughan]

What car/engine do you have, can you take a trigger scope at idle and attach a copy of your tune please.

[MIkedaf]

It’s a Ford Cosworth 2ltr engine. I will try and get a trigger scope in the next few days and attach.

thanks

[MIkedaf]

I have now got the trigger file which is attached.

I also looked into the log files in more depth and have noticed that the trigger 1 signal is being lost momentarily when the throttle is closed. 

If you look at the attached log at the time -0.05.186 you will see the throttle close and trigger 1 signal drop.

any Help appreciated

TriggerScopeLog 4.llgx base map 09.06.23.pclx ECU Log 2023-06-9 3;26;37 pm 7.llgx

[essb00]

What's the engine RPM when you captured the attached triggerscope? If it was captured as with the idle speed on your log, the arming voltage for Trig2 is getting reached by the noise on your captured triggerscope. You'll need to increase the arming voltage on Trig 2. Try to adjust to the following:

[MIkedaf]

Hi, it was at idle so will give that a go at the weekend and post the results

Thanks

 

[Adamw]

You can also increase your filtering on trig 1 & 2 to level 3.  

If the arming threshold and filtering adjustment doesnt help, try doing a bunch more scope captures around the rpm or whatever that it normally occurs at to see if we can get any more obvious clues captured.  

[MIkedaf]

Hi all,

Tried both the above suggestions and it doesn’t seem to loose trigger 1 now after running it for 10 minutes and blipping the throttle and it used to do it every throttle blip. Thanks for you help on this.

On another subject, trying to set the AFR target table axis to match the axis on fuel table 1 and it won’t let me. Am I  missing a setting somewhere?

[essb00]

AFAIK, AFR/Lambda table is just limited to 14x10 cells. You could just put ballpark X/Y axis figures as values in between would always be just interpolated by the ECU.

[MIkedaf]

Thanks all for the help