Is there a way to make $8D open-loop at idle, or at lease below a certain RPM range?

I'm working on an interesting project. A friend has installed a Chevy 350 into a 1933 Dodge pickup. He has pieced together a TPI setup and has asked me to tune it.

So far after troubleshooting it and finding some wiring errors, things are looking pretty good. I would however like to set the calibration to where it will not attempt to use any O2 feedback at idle.

Is there a way to set the tune up so that it will not use the BLM or integrator at idle, while still operating CL on the rest of the calibration?

Thanks,
David

 

there should be a scaler for forced open loop idle under a certain rpm

 

Thanks for the reply! I looked through my definition and the only things I see that mentions idle and CL are:

"IAC Command Engine Speed Open Loop Offset" at addres 631 hex.

The factory AUJP calibration I opened has it set to 1000. I was idling below 1000 and could see on the ALDL scanner that the short-term fuel trim was still active and moving around.

There is also a "Idle Open Loop % Change AFR" at 41F hex. Factory had it set to 0.

The parameters are not clearly labelled for a new-to-$8D guy like me.
The XDF is imported from Super_8dm2.ecu from Craig Moates site.

I feel like there is a way to make it open loop idle and I am overlooking it or the definition does not have it called out.

Thanks again!
David

 

I don't recall anything for an open loop idle in $8D. To do this you will need to add it to the code.

RBob.

 

i have it in my scalers but im using S_AUJP lol

 

There is no easy way to do that unless you use the S_AUJP V4.
It has the ability to set RPM range for idle (entering and exiting RPMs)
There is a bit to set if you want to use the idle SA table as well or just run from the main table at idle.
Stock AUJP idle is limited to 800 RPM maximum in the code so entering anything higher get pushed back. This is also corrected for and adjustable in the S_AUJP V4 bin.
If you go that route, be sure to check the "V4 Released" thread and start with the 1026 version to make the couple edits to the supplied definition files as indicated.
Jp

 

If you are idling rich you can adjust the O2 constants up by 50 mV in the three idle settings.
That will help with the stock tune if that is the primary problem.
496, 497, & 498 are the locations for these.

 

Thank you guys! I downloaded S_AUJP v.4 and the .xdf for it. It has the constants I needed!

That helped me but not as much as I needed. About to post another thread about it.

Thanks again,
David