Disabling AFM on 2011 Avalanche

[ntrimm]

I am hoping someone can explain in detail the exact steps I would need to follow to disable AFM (Active Fuel Management) on my 2011 Chevrolet Avalanche 5.3L. Is it as simple as pulling up the stock tune and going to the AFM tab and selecting DISABLE then saving and loading the new file?

Thanks

[Taz]

As a disclaimer, I’ve never tuned an AFM equipped engine. It appears setting B0921 to “No” should disable the AFM.

Additional options include:

B0961 (AFM Gear Disable) - have the option to disable AFM in all, or selected gears
setting B0931 to B0936 to a high RPM (ie. 8000), while also setting B0941 to B0946 to a low RPM (ie. 400)
setting B0960 to “0”

Again, just “thinking out loud” - have never tuned an AFM engine.


Regards,
Taz

[ntrimm]

Taz,
That's what I was thinking but wasn't sure if the B0921 needed to be NO or YES. It appears that changing that B0921 to NO is the extent of disabling the AFM. In the description above the value boxes it says " used to enable or disable the AFM V8 <>V4 functionality. I am going to buy a V2 scan tune so I can do this. I guess when I download the stock tune I will need to change the B0921 value to the opposite of what's factory tuned??? Hopefully this will work?

[Taz]

Looks like setting B0921 to “No” should disable the AFM. If for some reason when you adjust B0921 it does not disable the AFM - then move on to the other options.

Also, B0961 looks like an interesting tuning option - you could disable the AFM in the lower gears, and leave it active in 5th and / or 6th gear - if this suited your purpose.


Regards,
Taz

[Mojo88]

What are the symptoms of AFM kicking in and out? And when does it activate? Does AFM kick in at low speeds, say 30 mph?

I also have 2011 Avalanche and it does not run smoothly under light loads, part throttle. It chugs and skips.

thanks

[GMPX]

It shouldn't even be noticeable, usually on the instrument cluster it shows V8 or V4 mode.

[Taz]

Hello Mojo88,

To view when, and under what conditions, AFM is active - in your ECM tune open the “Engine Operation” folder, then the “Active Fuel Management” folder - all the viewable parameters are there.

If you don’t have access to your own ECM tune, there are several tunes on the Holdencrazy site available for download with AFM.


Regards,
Taz

[minytrker]

Yes, just clicking that box will disable it. I have had way more people want me to disable AFM than want me to leave it on when doing tunes. IMO the vehicles run better with a good tune with AFM turned off vs even tuning the AFM tables atleast where I live, it could be differnt out in the plains or somewhere 100% flat. In my G8 I was able to actually get better fuel mileage with AFM turned off all the time than having it use it. I also dont have exhaust drone now either.

[Mojo88]

Thanks gents