Lean Cruise

[joecar]

Look in the CAX subforum.

[nfs13b]

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]

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.
  
  
  1. Injects less fuel into the motor, so you consume less fuel and make less power.
  2. 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]

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]

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]

latest.tun
Here is a copy of my tune file..

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

Thanks
Lee

[Taz]

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]

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]

Yes, you can rename the .cax file but only if the COS came from that OS.