Lean Cruise with COS5?

[ferocity02]

I'm currently running COS5 2bar OLSD, but will probably go to the semi-open loop (SOLSD) soon once the VE table is good.

Lets say I have B3647 set to 1.0 in the cruise area, so normally it would be in SOLSD. And I have lean cruise enabled to remove 0.09 from the EQR (gives ~15.6 AFR assuming E10). Once the lean cruise enablers are met, will it completely ignore B3647 and also no longer attempt to use the STFT's for trimming?

[andysc3]

I just have my commanded fuel tables command richer in my cruise tables. I have my tune posted in my g/cyl thread if you want to take a look at how mine is. But I'm running a cos3

[ferocity02]

You're doing a rich cruise?

[andysc3]

Oops. I ment lean. Commanding 15.6. I like to keep my tunes simple. I don't like having to rely on other tables to trigger to get the lean cruise to activate.

[ferocity02]

Yeah that would be simpler, but I like the idea of setting the speed and ECT enablers for lean cruise so its not trying to go lean while puting around town and bucking.

Just want to make sure the semi-open loop isn't going to try to be active during lean cruise.

[Chevy366]

I ran a COS3 tun with Lean Cruise. Seemed to work fine.

[andysc3]

No surging issues here. My rpm/mph and kpa is very predictable and makes it easy to tune that way

[ferocity02]

No surging issues here. My rpm/mph and kpa is very predictable and makes it easy to tune that way

With a manual gearbox the surging/bucking is far more noticeable. Decelerating when lean is the worst. I need to richen up decel or re-enable DFCO.

[andysc3]

Mine goes rich on decel. I need to figure that out. It does down to 11.5-12.5. But I'm running FIC 1000cc injectors and I can't control the min pulse with

[ferocity02]

Mine goes rich on decel. I need to figure that out. It does down to 11.5-12.5. But I'm running FIC 1000cc injectors and I can't control the min pulse with

Yeah I had that issue too with their injectors, their data is not correct. Pm me for more info.

[5.7ute]

Once lean cruise is active it will not use semi open loop trimming. If you watch the Commanded EQ when lean cruise kicks in you will see that commanded goes away from stoich, preventing SOL from being active.

[ferocity02]

Yup, just enabled lean cruise today and saw that happen when it leaned out. Pretty neat!

[tinindian]

I loaded COS5 the other day and can't get lean cruise to work. The attached cax file (02020005.cax) is in C:\Program Files\EFILive\V7.5\Calibrations and the attached cal_link file is in C:\Program Files\EFILive\V7.5\Configuration. Lean cruise is enabled and was working in the stock-OS based tune I loaded after flashing COS5. Not sure what I'm doing wrong, any suggestions are appreciated.

[Chevy366]

Have to do full flash when LC is activated by .cax, then do normal cal flash to fill in the rest like regular COS procedure.

[tinindian]

Yes, the file 02020005.cax was in place when I did the full flash of COS5. Then I cal-only flashed my previous tune file from the original OS. B9001 is enabled and I have valid numbers in the lean cruise tables & parameters. When I drive over the LC activate speed the commanded AFR does not change, like it did before I went to COS5.

Do I need to do something else - besides having the cax file in place - when I do the full flash to activate LC?

[joecar]

Yes, you have to enable LC, save file, and then do a full flash of this file, as Chevy366 said above.

Then you have to populate the LC tables and do a cal flash.

[tinindian]

Got it, thanks. I just had to do a full flash with the file I've been using. So the process is: full flash of the COS with cax file in place, cal only flash the latest tune file from the original OS, save the tune file, then full flash that tune file.

[joecar]

You already have a current COS tune file
(i.e. you already full flashed in the COS, you already cal flashed from the original OS to populate the COS, you already read back the COS from the PCM and saved to file... you may have done further edits and flashes, and now this is your current tune file);


within your current tune file, enable LC and do a full flash, then populate the LC tables and do a cal flash.