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View Full Version : Idle speed.. how?



ringram
April 7th, 2008, 08:15 AM
Ok Ive dropped desired idle speed to 700 rpm on a stock LS2
Ive also reduced minimum idle airflow in neutral.
But its still idles at 800rpm.
Strangely when coming to a stop (ie) still rolling idle drops to 700. But as soon as I stop it rises to 800 again.

Anyone have any joy changing E38 idle speeds want to share the beans?

ringram
April 23rd, 2008, 01:20 AM
Update: Definately seems to be not enough tables in the cals for this.
Halving airflow still makes no difference, in fact the minimim airflow "seems" to work for rolling idle and not static idle of B1817/B1818 as when rolling to a stop idle drops to about my commanded level. But almost at a stop it jumps back to default 800.

Blacky
April 23rd, 2008, 07:38 AM
What version of EFILive are you running: V7.5.3 or V7.5.4?
What is the version number of the *.cal file that you are using? That shows up on the first window when you open the *.tun file.

Regards
Paul

ringram
April 23rd, 2008, 09:06 AM
754 build 48
Will edit this post with cal version tomorrow, but its the calz ones from the 14th April beta bbl update.

Blacky
April 23rd, 2008, 09:23 AM
That's the latest cals, I'll PM Ross to see if he has any more info...
Paul

Redline Motorsports
April 23rd, 2008, 12:36 PM
I have seen the same.

Howard

hymey
April 25th, 2008, 12:42 AM
Have you adjusted the idle over and underspeed corrections. I found these need to be aggressive to smooth idle to desired setting. Start with 3 degrees and work up to 7 degrees either side. ie low idle correction will add more timing high idle correction will remove timing. Not sure if this is your problem but it worked in mine.

GMPX
April 26th, 2008, 11:12 AM
Richard, via scanning can you determine if it's spark or throttle movement (or both) causing it.

Cheers.
Ross

ringram
April 29th, 2008, 04:37 AM
Will check mate. Car currently at dealers waiting warranty replacement of manual trans :)
Vauxhall dude needs to check apparently. Not my fault, it was already bust, honest.

ringram
April 30th, 2008, 06:50 AM
Richard, via scanning can you determine if it's spark or throttle movement (or both) causing it.

Cheers.
Ross

Hi mate, it looks like throttle opens up more, from 16.9% at 700rpm when coming to a stop to about 18.4% at 800 when I go under B1817 or maybe B1818

(ie) Rolling idle is correct, but near static and static idle goes back to 800 stock rpm.

The old BBL firmware made a mess of my logs so Ill see if I can get you one tomorrow with the new FW.

hymey
May 1st, 2008, 04:55 PM
Any results?

ringram
May 10th, 2008, 11:11 PM
I have a log file from just rolling down a hill in neutral, showing throttle opening and closing as I trigger the 6kmph value in the B181x cell as above.

(ie) Table appears to work as rolling idle and not static idle.