DFM disabler released

[21RST]

Honesty no, because I don't return stuff very often.

I did however read the description of what they said it does and it said "all cylinders, all the time". Which I later found out to be a lie (and they knew it was lie before sending out the very first device).

Having been a long time gear head I mistakenly assumed Holley was still a reputable company (I've used their products for literally decades). Apparently since they're now owned by Sentinel Capital partners (a private equity firm, because private equity firms do great things in the automotive aftermarket industry,,, just look at what private equity did for Wheel Pros and all their brands like Hoonigan and 4 wheel parts) they are now Holley in name only, and are just another company selling stuff based off brand recognition, from a brand they purchased.

To be clear, all I want is the product to do what they said it would do, nothing more, nothing special, just turn off the DFM. And YES i am 100% going to tell everyone I can, every chance I get, what a rip off, lying, and under-handed company that Holley (or more correctly Sentinel Capital Partners) is now.

They ripped me off, and yes that pisses me off. Best I can do is hope that I can help to prevent them from ripping off the next guy.
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Do you want to sell it?

 

[Antonm]

Do you want to sell it?

Maybe, want to see if there is a scan tool that can confirm (or deny) the statements in post #238 above first though.
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[21RST]

Maybe, want to see if there is a scan tool that can confirm (or deny) the statements in post #238 above first though.
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Understand. Just let me know.

 

[Scarey]

?

 

[ninjaplumber]

Launch Scanner

 

[fondupot]

Launch ScannerView attachment 444767

Cool. I have a similar Launch reader. Not the exact one in the video. I’ll have to look and see if I can do that with mine.

 

[21RST]

Yeah somebody needs to try that with the range module.

 

[Scarey]

I think Dfm is not active during decel. I think Dfm is a piece of software in the ecm to selectively deactivate, collapse lifters, cylinders. I think decel is a different piece of software. I think decel uses lifter “ collapse” to deactivate cylinders along with fuel cutoff and ignition. So to say decel is not Dfm is correct. In the end I believe cylinders are being deactivated during decel. My guess, how do we find out?

 

[Marky Dissod]

I think DFM is not active during decel.
I think DFM is a piece of software in the ecm to selectively deactivate, collapse lifters, cylinders.
I think decel is a different piece of software.
I think decel uses lifter “ collapse” to deactivate cylinders along with fuel cutoff and ignition.
So to say decel is not DFM is correct.
In the end I believe cylinders are being deactivated during decel.

My guess, how do we find out?

DFM / Cylinder (Valve) Deactivation may - or may not - be active during decels; some yes, some no.
Decel is a subroutine. Decel Fuel Cut Off is another subroutine. Not all decels are DFCOs. Every DFCO is a decel.

Decel is when your foot is off the gas and the TCC is unlocked. A minimum of injected fuel keeps the engine idling.
Closest you can get to neutral without shifting into neutral.
So long as the engine is warm enough, decel can use less than 8 cylinders.
If the engine needs to warm up, decel can use up to 8 cylinders.

DFCO is when your foot is off the gas and the TCC is LOCKED. The road, through the trans, runs the engine.
No fuel injected, yet cylinders still try to suck air through a closed throttle, which is technically engine braking.
DFCO would NOT deactivate any cylinder valves, because there's already decel for 'no engine braking desired'.
DFCO is in the highest gear possible, no downshift.
Powertrain braking is DFCO, PLUS at least one downshift. More downshifts = more powertrain braking.

Hope this helps.

 

[Scarey]

I’ve given up trying to figure this out. I’m pissed I spent allot of money for this Rube Goldberg machine. Thanks GM.

 

[RG23RST]

Yeah somebody needs to try that with the range module.

You need a scan tool with oscilloscope functionality. DFM solenoids are peak & hold style when active. When it’s not active there’s always some millisecond level current pulsed through the solenoids to purge air from the oil circuit to the lifter body. Even running around in L9 this behavior is still present.

 

[Antonm]

I’ve given up trying to figure this out. I’m pissed I spent allot of money for this Rube Goldberg machine. Thanks GM.

GM didn't want to spend the time, or spend the R&D money, to make this crap-tastic system happen, they were forced to come up with something by our tyrannical EPA and the ever changing CAFE standards the EPA imposes.

Just like most car manufactures don't really want to jump into EV's because they know they don't sell or and when you actually do sell one, it doesn't make the same margin here in the US. But they need them in their lineup for compliance reasons/ carbon credits so they can still make/ still sell the vehicles that do make them money.
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[Marky Dissod]

GM didn't want to spend the time, or spend the R&D money, to make this crap-tastic system happen,
they were forced to come up with something by our tyrannical EPA and the ever changing CAFE standards the EPA imposes.

No matter what anyone does to 'improve' MpGs, fact remains, our SUVs are
80" wide, over 6' tall, 5000lb / 6000lb bricks.
Newton's laws demand a certain amount of energy be expended to move 'em.

Cylinder valve deactivation and 10speed transmissions are pretty much the proof that
we've crossed the point of diminishing returns in terms of squeezing more MpG from a drop of fuel.
One way or another, end users will pay for every single 'technology', whether it works or not.

 

[fondupot]

I tested with my Launch Creader tonight on a ~30 minute drive, reading live data of the cylinder deactivation system. There were 0 cycles reported on the scanner for the entire drive. I gotta figure out how I can download the report and post it here though.There were also some other live data settings related to the DFM i could read, so I will do another test tomorrow or Saturday.

I have RA007 module installed.

My truck has stock exhaust. If I listen carefully I can hear the 0-cylinder decel/coast mode engage. But as stated, the scanner indicated no cycles of the cylinder deactivation system.

 

[Scarey]

?

 

[Scarey]

I tested with my Launch Creader tonight on a ~30 minute drive, reading live data of the cylinder deactivation system. There were 0 cycles reported on the scanner for the entire drive. I gotta figure out how I can download the report and post it here though.There were also some other live data settings related to the DFM i could read, so I will do another test tomorrow or Saturday.

I have RA007 module installed.

My truck has stock exhaust. If I listen carefully I can hear the 0-cylinder decel/coast mode engage. But as stated, the scanner indicated no cycles of the cylinder deactivation system.

If you could drive the same course with RA007 removed and compare the two. I think the results would be very conclusive.

 

[fondupot]

I'll try to get around to it.

 

[23Seven]

I hate to be that guy but here’s my experience. I got the Range DFM this morning and installed as directed. First drive was cool, auto stop was disable and it was staying in V8 mode. I went for a 2nd trip for gas and when I re-started the truck I had an engine light. I came home and pulled the Range off but the engine light remained on and on top of that I was getting a bell and message to release the parking brake every-time I started moving from a complete stop. I tried to clear codes through the OBD2 but that was a no go! Called OnStar and had them run a diagnostic and they said to check the fuel cap, LOL it doesn’t have a fuel cap. I ended up taking the negative terminal off for 10 minutes and hooking it back up. I got lucky and that reset everything and everything is on point and 0 codes. I’m sending it back for a refund and counting my lucky stars that it didn’t screw up my truck!

2024 Z71 with a 6.2.

They got more work to do on this module, I used the AFM in my 15 Vette and it was great but this one is crap!

 

[23Seven]

I hate to be that guy but here’s my experience. I got the Range DFM this morning and installed as directed. First drive was cool, auto stop was disable and it was staying in V8 mode. I went for a 2nd trip for gas and when I re-started the truck I had an engine light. I came home and pulled the Range off but the engine light remained on and on top of that I was getting a bell and message to release the parking brake every-time I started moving from a complete stop. I tried to clear codes through the OBD2 but that was a no go! Called OnStar and had them run a diagnostic and they said to check the fuel cap, LOL it doesn’t have a fuel cap. I ended up taking the negative terminal off for 10 minutes and hooking it back up. I got lucky and that reset everything and everything is on point and 0 codes. I’m sending it back for a refund and counting my lucky stars that it didn’t screw up my truck!

2024 Z71 with a 6.2.

They got more work to do on this module, I used the AFM in my 15 Vette and it was great but this one is crap!

I’ll turn off auto stop manually and run it in L9 moving forward.

 

[fondupot]

@23Seven thats really strange. Mine has been flawless since installation. No errors. No CELs. Just smooth V8.