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jamesbond2509
September 6th, 2010, 01:20 AM
I have been searching the threads on lean cruise and am interested in getting better mileage. It seems like updating B3647 can accomplish this instead of using the patch. Any thoughts.

Regards,

GMPX
September 6th, 2010, 10:35 AM
There is an easier way, there was a patch someone released as a .cax file that activates the factory lean cruise tables on non Holden vehicles. It might take a while but if you search this forum for Lean Cruise the thread should appear.

Cheers,
Ross

Taz
September 6th, 2010, 11:09 AM
What OS are you running ? Your truck is a 2002, so probably 12212156 ?

Depending on your OS, I may have a *.cax file that will work.


Regards,
Taz

jamesbond2509
September 6th, 2010, 11:29 AM
Im running COS 02020003.

What are the pros & cons of justing using B3647 vs actually programming in the lean cruise.

Regards,

5.7ute
September 6th, 2010, 12:29 PM
Since you are already using a COS I would just set B3647 to your lean AFR in the cruising cells. The reason being is that some COS's have an issue where a rich cruise mode can occur.(this happens if an enriched cell in B3647 is being used when lean cruise becomes active) There are obviously some lean cruise enablers that are not defined to cause this but I havent had time to track them down as yet.

jamesbond2509
September 7th, 2010, 01:35 PM
After further review I kinda like the lean cruise features better than the B3647 but sounds like it is going to be difficult or not possible to set up with a COS? Please advise

Thanks

5.7ute
September 7th, 2010, 01:50 PM
It can be set up. In my case I needed to ensure that I was only commanding around stoich up to around the 80kpa column at cruise RPM. I have had lean cruise come active through the enablers around this manifold pressure when commanding 13.0:1 AFR(was a looong time ago so not 100%). The result was a commanded AFR of 13.0:1 at cruise with an actual AFR richer than stoich. (commanded AFR gets locked & the fuelling modifiers adjust the PW independant of this.)
It will not do any harm to get lean cruise operational & take some logs to ensure this doesnt happen on your OS.

L31Sleeper
May 4th, 2011, 12:12 PM
I have been searching the threads on lean cruise and am interested in getting better mileage. It seems like updating B3647 can accomplish this instead of using the patch. Any thoughts.

Regards,

I know this is somewhat of an old thread, but I did exactly that and it worked like a charm!!!
You have to have your VE table SPOT ON, then run Open Loop. Who needs O2 sensors anyway.
I kept an eye on my Wide Band O2 Just to make sure everything was working properly.

smslyguy
August 6th, 2011, 09:05 AM
Do you have the lean cruise patch for an 01 ls1? Or is any patch found on here good for any pcm? Also where does the lean cruise patch get downloaded to? usser configeration?

GMPX
August 6th, 2011, 09:47 AM
Do a quick search because the patch info was re-posted on here within the last month. It's simply a .cax file you save in to a directory and away you go (instructions were in the zip).
It's suitable for any OS from 2001+

joecar
August 6th, 2011, 12:41 PM
Look in the CAX subforum.

nfs13b
August 15th, 2011, 09:37 AM
Hey,

First up I pretty much know nothing about using this software yet :( I have a 2003 Silverado 2500HD with the 6litre engine and its on LPG. My tuner(from USA) says my car hasnt got the lean cruise option but I had someone in Australia previously tune the car on a mafless tune (car is back to a maf tune) and that guy said he set up the lean cruise in his tune.. He said when you took your foot off the accelerator it would stop the injectors or something like that....

I am trying to get another 40km from a tank of LPG as I have an 85litre tank and I am currently getting about 320-330km from a tank...

Thanks heaps
Lee

swingtan
August 15th, 2011, 10:24 AM
Sounds like you have a couple of things confused here.


Lean Cruise is a condition where you command a leaner than stoichiometric mixture at very light throttle. The result of this is does two main things.


Injects less fuel into the motor, so you consume less fuel and make less power.
Makes you increase the throttle opening, to get a little more power, but that also reduces the "pumping losses" of the motor.


the combined effect is to gain additional mileage from the vehicle.

Deceleration Fuel Cut Off, or DFCO turns off the injectors altogether when the engine is in an over-run condition. For example, coming to a stop or rolling down a steep hill. In these situations, there is sufficient momentum in the vehicle to keep the engine turning over so no fuel is needed to prevent a stall.

The result of this is increased mileage from the vehicle.



If you drive a lot in flat open terrain, then lean cruise is more likely to give improvements in economy. If you drive in hilly, winding or built up areas, then DFCO is more likely to give good improvements.

The two functions are exclusive in their operation, but both can be set up in the tune.

Simon

nfs13b
August 15th, 2011, 10:43 AM
ok definitely have things confused then....

So can I get lean cruise on my Silverado and how do I check if the DFCO is set up?

ScarabEpic22
August 16th, 2011, 02:17 AM
DFCO is always setup from the factory, your tuner probably adjusted the settings to make it become active earlier and stay on longer. Post the tune up.

Need to see if your OS is supported, then go into the .CAX subforum on here and download the .cax file for your OS. Copy the .cax to "C:\Program Files\EFILive\V7.5\Calibrations". Then an option will be available to enable lean cruise.

nfs13b
August 16th, 2011, 08:39 AM
11703
Here is a copy of my tune file..

From the file it says my OS is 03150003.... is that right?

Thanks
Lee

Taz
August 16th, 2011, 10:05 AM
Hello Lee,

That OS is an EFILive COS (Custom Operating System) - you cannot use a LC (Lean Cruise) *.cax file with a COS.


Regards,
Taz

Chevy366
August 17th, 2011, 04:42 AM
Hello Lee,

That OS is an EFILive COS (Custom Operating System) - you cannot use a LC (Lean Cruise) *.cax file with a COS.


Regards,
Taz
Can't you rename the .cax to the COS number and it work ? Like : 03150003.cax .

joecar
August 17th, 2011, 06:07 AM
Yes, you can rename the .cax file but only if the COS came from that OS.