when is an LBZ idle fix planned?

[Black6spdZ]

Idle table only adjusts idle at a stop and no A/C.. if the idle is set lower than stock "680" you get a surge as soon as you start to roll or the A/C engages.. this gets particularly annoying at times.

[GMPX]

Was not aware it was an issue.

[Black6spdZ]

I put in a low priority ticket in April http://support.efilive.com/view.php?ticketref=8429-QPSG-8480 but first noticed it long ago. I am surprised no one else has brought it up. It doesn't seem to affect the LMMs. I dunno..

[THEFERMANATOR]

It has been brought up before on other forums, most have just learned to live with it. I know I turn the idle down on LMM's, but as seen as it senses any RPM to the driveshaft it raises teh RPM's right back to 720 instead of 680 where I set it at. Just one more thing I like about my LB7 as I run a 600 idle on it.

[StinkyDog]

Sometimes inadvertently increasing the P.W. in the idle cells will result in a lope. I just had that issue crop up. Returned those cells back to stock and all is well :)

[killerbee]

Idle table only adjusts idle at a stop and no A/C.. if the idle is set lower than stock "680" you get a surge as soon as you start to roll or the A/C engages.. this gets particularly annoying at times.

There is probably an unreleased idle adjustment for AC, that would make a lot of sense. It exists on other year groups.

If you want to log rpm, pulse and actual pressure, and post the log here, it might help. Smoothing of the pulse table can be warranted, as lowering rpm often increases pulse and mm3. If act pressure is dipping, then the pulse lope (instability) can get worse as you head toward the 20mPa column. But a log is needed to give accurate direction.

[bballer182]

I have had my LBZ idling @ 650rpm for a couple years and have not noticed any of what you describe, even with a/c on...???

[Black6spdZ]

any ETA on a fix for this? or is EFILive leaving the Duramax for good in favor of Cummins

[LB72004]

Just one more thing I like about my LB7 as I run a 600 idle on it.

i'll probably get flack for this but i run mine at 500 RPM.

[bballer182]

i'll probably get flack for this but i run mine at 500 RPM.

Why would you get flack for that? Its your choice to ruin you engine with a ridiculously low idle speed. It doesn't affect any of us... :)

[THEFERMANATOR]

Why would you get flack for that? Its your choice to ruin you engine with a ridiculously low idle speed. It doesn't affect any of us... :)
Others have run them down to 450, so it isn't a worry.

[bballer182]

Others have run them down to 450, so it isn't a worry.

I'm not picking a fight but, says who? Who says idling them at 450 is fine? An engineer? A reputable engine builder? Personally I've run the a calc pid and there is no fuel savings to run them that low. And most of all I'd be worried about harmonics tearing apart crank and bearings. But that's just me do what you want.

[THEFERMANATOR]

I'm not picking a fight but, says who? Who says idling them at 450 is fine? An engineer? A reputable engine builder? Personally I've run the a calc pid and there is no fuel savings to run them that low. And most of all I'd be worried about harmonics tearing apart crank and bearings. But that's just me do what you want.
Just said it's been done without ill effects. I know GM set them at 600 for 01 yet the engine has a NASTY harmonic in it at 620-660. I know quite a few others have run them down to 550. I personally run 600 on mine as I see no advantage to running it any lower.

[bballer182]

Just said it's been done without ill effects. I know GM set them at 600 for 01 yet the engine has a NASTY harmonic in it at 620-660. I know quite a few others have run them down to 550. I personally run 600 on mine as I see no advantage to running it any lower.

Immediate I'll affects. ;)

[LB72004]

this is kind of what i meant, but i will have to admit that this site is a lot tamer the others that i visit.

[cindy@efilive]

We've looked at the comments in this thread and the historical reported incidents (or lack there of). There will be no review of the underlying code at this point. To do so exposes a greater range of customers who either do not have this issue, or have an effective tuning strategy to prevent it. It should also be mentioned that the underlying code has been static in its current form for the best part of 4 years.

This position would change if there was a measurable increase in reportable instances.

Cheers
Cindy

[Black6spdZ]

We've looked at the comments in this thread and the historical reported incidents (or lack there of). There will be no review of the underlying code at this point. To do so exposes a greater range of customers who either do not have this issue, or have an effective tuning strategy to prevent it. It should also be mentioned that the underlying code has been static in its current form for the best part of 4 years.

This position would change if there was a measurable increase in reportable instances.

Cheers
Cindy

I can understand from your point the R&D time needed is not cost effective for the dwindling amount of older LBZ vehicles and out of them those who actually tweak on idle speed and would have this issue. BUT, if you say this code has been static and mature for a better part of 4 years and has still had this issue without being resolved we might as well not have an idle speed adjustment if it doesn't function correctly and will most likely never will at this point in time. I don't think there is any method to "tune" it out as I mentioned in this thread and the trouble ticked I put in a good two years ago, as soon as the A/C clutch engages or you begin rolling the base idle goes to the factory "680" idle preset irregardless what you set in B0701.