How do i disable DFCO? (Deceleration Fuel Cutoff)

Hi guys, I?m trying to disable DFCO (deceleration fuel cut off) in my tune. I want fuel to continue on deceleration to promote pops and bangs out the exhaust, as well as between shifts. Please don?t ask why or tell me reasons not to, I simply want to know how to disable it all together.

Write up from HP Tuners: ?DFCO must pass a series of enable tests to even be considered. If any of the tests are not passed, the DFCO process will not be started. (Fuel is still on)?

I have noticed when I first start my car cold before DFCO kicks in it pops and crackles a lot. I think there is a temperature-based DFCO that activates pretty quickly after the car warms up.

Where can I change this in HP Tuners? I?ve looked under fuel>fuel cutoff and its only RPM based conditions. I believe I?m looking for some kind of temperature based setting. I don?t want to mess with timing and such, just simply disable DFCO!!!

Any help is much appreciated :) Vehicle is a turbo Cobalt SS

Use the Navigator Ctrl+N enter ECT
Attachment 90309

badwolf - the lnf ecm doesn't have traditional charts like that

julian vm - on the lnf ecm if i remeber correctly its under torque management/general/etc limits. that chart controls injector operation during torque management - i think thats the chart that controls the dfco on that ecm. you'll want to zero out columns 0-2 and leave 3 all at 15. thats how some past tunes that ive seen had it but i suppose you can zero it all out. double check what im saying since its been a little bit since ive messed on a lnf ecm.

The description for that section is ?Defines which cylinders will be disabled for torque management. Set to 0 to disable cylinder cut.?

I?m not totally sure what that means, but it doesn?t sound like traditional DFCO? I want to stop the cutting of fuel. What exactly is a cylinder disable?

yes you will want to zero out the table to keep the injectors active. that table controls injector operation. so if you zero that table out your telling the ecm to keep the cylinders active meaning injectors still spraying

Okay i just tried what you said with the column numbers. I did a bit more research and it seemed like the way to do it. On first test around the neighborhood, nothing seems different... popping is the same as before. Did something go wrong here? It said it successfully wrote to the PCM...

You will have to log spark advance on a engine load vs rpm histogram like it has in the tune to see where exactly you fall in during a coastdown/in gear and retard the timing in those cells. I make all the timing charts the same

I was hoping to not get into messing with the timing. I thought DFCO would be enough to induce the effect i want. Its strange because the car makes the sound I want only during the first minute of driving, and then totally quiets down. If its already warm or its a warm day out then it won?t pop at all, or just for the first 10 seconds or so of driving. Still sounds like a temperature based DFCO is still active in my case. I?m really not sure :(

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Originally Posted by Julian VM

I was hoping to not get into messing with the timing. I thought DFCO would be enough to induce the effect i want. Its strange because the car makes the sound I want only during the first minute of driving, and then totally quiets down. If its already warm or its a warm day out then it won?t pop at all, or just for the first 10 seconds or so of driving. Still sounds like a temperature based DFCO is still active in my case. I?m really not sure :(

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You have to really check all the stuff under DFCO, because my car wont turn it off until all the parameters are just right