L83 2014 GMC Sierra 1500 5.3l TPS for DFCO table on HPTuners

[Sloop1210]

Hi everyone,

This is my first post here and actually the first time I actually look into the engine ECU of my truck. So, I have a 2014 GMC Sierra 1500 5.3l which I believe is a L83 engine. I also have HPtuners with an MPVI3. I originally bought HPTuners because the cats have been deleted by the previous owner of the truck and I didn't want to have the MIL on all the time. So, I downloaded the software from the ECU, disabled the Fault codes that were annoying and re-flashed the new software. It worked, I am happy. It's great. But, now, I think it's a little sad to have paid the credits for HPtuners and not learn more about the engine management/tuning.
So, I picked an easy subject/goal to start and it's a "burble" map. Don't judge me, I never said I will keep it, I know it's pretty much useless and it can be harmful for the engine if done wrong but I want to look into it.
My issue, is that from what I researched online, I need to modify a table called "DFCO Enable TPS vs RPM" or it's equivalent to make sure that DFCO isn't enable even when TPS will be at 0. Unfortunately, I can't find that table and I don't know what the equivalent will be on my ECU.

Anybody can help?

Thanks in advance

[[email protected]]

Assuming you have a E92 ECM it would be engine>fuel>cutoff DFCO and there should be several tables for you to change. I'm also assuming you are using advanced view in edit>view>advanced.

[Alvin]

Why are you wanting to adjust DFCO? That isn't where I'd start on this.

[Sloop1210]

Hi Alvin,
Thanks for the answer.
My understanding is that DFCO is the function that cuts fuel injection during deceleration (throttle at 0%). So, you lift off the gas pedal, the fuel injection is cut and you save some fuel.
Or, for a burble map, I need fuel in the cylinder and a modified timing to have actual ignition later than usual.
From what I've seen in the ECU, my truck has a DFCO activation above a certain speed (per gear) and a de-activation below a certain speed (again, per each gear).
So, my understanding was that I need to de-activate DFCO to make sure that fuel will still be injected.

Am I right or did I miss/misunderstood something?

Thanks in advance for your answer and comments.

Have a good day.

Alain

[Alvin]

There is very little to no gains in fuel mileage for DFCO.

That might sound counter intuitive but in DFCO the engine is effectively engine braking. If you want your coast down to be a harder brake down than would be otherwise than DFCO is the way to go.

I find mileage in these by increasing timing where I'm able while avoiding knock.