$OD Lean Cruise

[trlrider]

To invoke a old thread, but did anyone ever get Lean Cruise to work in a $0D or $E6??

[444]

I haven't played with it yet but there is the open loop afr vs temp vs vacuum table and the associated qualifiers that look like you could setup to open loop lean cruise. The description says it can also be used in closed loop mode but I'm curious as to what happens if you do that and the computer is calling for 16:1 closed loop afr with a narrowband o2 sensor.

[trlrider]

I haven't played with it yet but there is the open loop afr vs temp vs vacuum table and the associated qualifiers that look like you could setup to open loop lean cruise. The description says it can also be used in closed loop mode but I'm curious as to what happens if you do that and the computer is calling for 16:1 closed loop afr with a narrowband o2 sensor.

Interesting! Thanks for pointing that out. That will be another notebook once I finally get this truck running well without the added tweaks. Eventually it will be making some long highway runs out of state and the added fuel mileage would be a huge bonus.
Learning as I go and trying to contribute when I can based on what I have learned.

[Fast355]

Interesting! Thanks for pointing that out. That will be another notebook once I finally get this truck running well without the added tweaks. Eventually it will be making some long highway runs out of state and the added fuel mileage would be a huge bonus.
Learning as I go and trying to contribute when I can based on what I have learned.

From memory from playing with the AFR lockup table eons ago, the PCM disables fuel trims when the air/fuel ratio commanded is different than stoich. I had the lookup tables enabled and the BLMs or INTs never moved.

[trlrider]

From memory from playing with the AFR lockup table eons ago, the PCM disables fuel trims when the air/fuel ratio commanded is different than stoich. I had the lookup tables enabled and the BLMs or INTs never moved.

you

FAST355, your input is greatly appreciated. I am learning this TBI/EFI stuff and have learned much from your post on this and the 3rd Gen forums.

[444]

I did some more reading and from what I gather, once you have your VE table perfectly dialed in stock/closed loop mode you can then set your calibration to run in open loop full-time. When you do this the computer refers to the open loop AFR tables and extrapolates fueling based on the assumption your VE table is perfect and = 14.7 AFR. Which if you think about it is pretty handy they did it that way.

Check out the pdf I attached. In it the author says what he did is scrapped the EGR valve, set EGR fueling modifiers to 0 and set the EGR timing modifier map to duplicate the extra timing the old TBI highway mode did. By monkeying with the EGR qualifiers you could set it add the extra timing only when at a steady high-map cruise with the engine at full operating temp. A neat work-around I would like to try!

[trlrider]

I did some more reading and from what I gather, once you have your VE table perfectly dialed in stock/closed loop mode you can then set your calibration to run in open loop full-time. When you do this the computer refers to the open loop AFR tables and extrapolates fueling based on the assumption your VE table is perfect and = 14.7 AFR. Which if you think about it is pretty handy they did it that way.

Check out the pdf I attached. In it the author says what he did is scrapped the EGR valve, set EGR fueling modifiers to 0 and set the EGR timing modifier map to duplicate the extra timing the old TBI highway mode did. By monkeying with the EGR qualifiers you could set it add the extra timing only when at a steady high-map cruise with the engine at full operating temp. A neat work-around I would like to try!

Have that Tuning .pdf printed and use for reference. It has notes written on the first several pages. LOL!

[Turnshredder]

I haven't played with it yet but there is the open loop afr vs temp vs vacuum table and the associated qualifiers that look like you could setup to open loop lean cruise. The description says it can also be used in closed loop mode but I'm curious as to what happens if you do that and the computer is calling for 16:1 closed loop afr with a narrowband o2 sensor.

I never got it to work always goes to 14.7, I don't see how a narrow band sensor could read much different, I messed with all the qualifiers and tables.