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DFM disabled

11bravoZ71

By 11bravoZ71
in Modifications, Wheels & Tires

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11bravoZ71 Enthusiast

11bravoZ71

Posted
Posted

Range OBD module VS pulsar LT 

 

does anybody know how these 2 products disable  DFM? 
 

I have the range module for my OBD port but it sometimes doesn’t keep DFM off I’ve already tired 2 different ones. It’s just not reliable to keep DFM off for good while installed  in my l84 5.3. I can the see the LEDS flicker all the time so it’s always fighting the signal to keep DFM OFF by design. And clearly sometimes fails 
 

does the pulsar LT actually disable it to the core? When installed. or is it the same idea,  always fighting the computer. Any ideas 
 

SPASierra Enthusiast

SPASierra

Posted
Posted

The Pulsar intercepts the signal from the computer to the engine, and tells it to stay in 8cyl mode.  

BlancoSilverado Enthusiast

BlancoSilverado

Posted
Posted
On 10/11/2022 at 2:35 PM, 11bravoZ71 said:

I can the see the LEDS flicker all the time so it’s always fighting the signal to keep DFM OFF by design. And clearly sometimes fails 

Do you mean that the OBD port is losing power or is only a few LEDs turning flickering?

11bravoZ71 Enthusiast

11bravoZ71

Posted
  • Author
Posted
On 10/11/2022 at 5:25 AM, GN2018 said:

You don’t have a friend in a State that you could ship the Diablo to and have that person mail it to you?

 

10 minutes ago, BlancoSilverado said:

Do you mean that the OBD port is losing power or is only a few LEDs turning flickering?

Not loosing power from the port.that I know of.  
 

I’m not sure what the lights mean. I just know that their always changing pattern. So I assume it’s constantly sending the signal to keep DFM off. 
it’s not a one and done vs a actual tune… I’m hoping the pulsar LT  stops DFM more robustly. Like a tune but without the tune as advertised obviously. 
 

im not a fan of that. I can still sometimes feel the truck changing from v8 to  everything in between every now and then. Not 100% reliable in my experience.. and I tried to 2 new range modules  that were updated. At least with this 5.3 l84 DFM engine. 
 

 

im going to try and try a pulsar LT for now and later try and get it tuned off permanently with a superchip tuner to anticipate a DFM hard delete. 

mwlewis558 Enthusiast

mwlewis558

Posted
Posted

I had the Range OBDII plug in and it would work a few trips and then I could notice that the DFM was working and when I come to a stop the auto stop/start would be active and I would have to unplug the unit and put it back in. I got annoyed with that after a while and bought the Pulsar LT about a month ago. It was super easy to install and program and it has been working just fine since day one. I recommend the Pulsar LT unit because it works all the time. 

  • 3 weeks later...
11bravoZ71 Enthusiast

11bravoZ71

Posted
  • Author
Posted

I ended finding a way to get my ECM unlocked from superchips. And got their tuner I disabled DFM with the tuner. And for sure it’s now OFF permanently. With the range module I was able to notice it would only work half the time I would coast then gas the pedal and I would feel the engine go into v8 very often and then not 

.

Now with this tune off  it’s just off period. instantly v8 feel. 
 

IMO. Those modules are always fighting the signals from the ECM to constantly block “AFM/DFM. It’s not just shut off. And I’ve tried 2 of them updated ones…. Theirs a reason why the LEDS blink back and forth. Maybe it’s just my truck idk. Or DFM is just more complex then AFM. 

 

Tuning it off actually reprograms so DFM doesnt even exist electronically.  At the ECM level. So No signal to block from the beginning. 
 

As a side benefit the transmission now  shifts even better and firmer a whole lot less lag 😁

 

 

Diamond817 Enthusiast

Diamond817

Posted
Posted
17 hours ago, 11bravoZ71 said:

I ended finding a way to get my ECM unlocked from superchips. And got their tuner I disabled DFM with the tuner. And for sure it’s now OFF permanently. With the range module I was able to notice it would only work half the time I would coast then gas the pedal and I would feel the engine go into v8 very often and then not 

.

Now with this tune off  it’s just off period. instantly v8 feel. 
 

IMO. Those modules are always fighting the signals from the ECM to constantly block “AFM/DFM. It’s not just shut off. And I’ve tried 2 of them updated ones…. Theirs a reason why the LEDS blink back and forth. Maybe it’s just my truck idk. Or DFM is just more complex then AFM. 

 

Tuning it off actually reprograms so DFM doesnt even exist electronically.  At the ECM level. So No signal to block from the beginning. 
 

As a side benefit the transmission now  shifts even better and firmer a whole lot less lag 😁

 

 

?? Are you saying superchips reprogrammed your ECM??

Diamond817 Enthusiast

Diamond817

Posted
Posted
7 minutes ago, 11bravoZ71 said:

Yes superchips unlocked my ECM. Then after I got it back from them I was able to tune the truck adjust other settings and disable DFM. 

What did you use to tune the truck and adjust settings?

11bravoZ71 Enthusiast

11bravoZ71

Posted
  • Author
Posted (edited)

 

 

I used the superchips tuner, part number 2847-S. Once you receive it in the mail you fill out a form online with instructions it was VERY easy to do. 
 

Then  I had to ship my  ECM to them to get it unlocked, it’s included in the price of the tuner to get it unlocked. I just had to pay to ship it to them…. they then ship it back really fast on their dime overnight. Then you can use that tuner. 

 
 

We’ll worth the investment If keeping the truck long term like I plan to. To disable that DFM with a permanent tune. If the motor still fails later from a lifter I’m rebuilding it with a DFM delete kit and will already have the tuned off portion done. 

 

https://www.holley.com/products/tuners_and_programmers/handheld_tuners/parts/2847-S?utm_term=&utm_campaign=Google+Shopping+-+SuperChips+-+Brand&utm_source=google&utm_medium=cpc&hsa_acc=7848552874&hsa_cam=13757689632&hsa_grp=125866783153&hsa_ad=531361842411&hsa_src=g&hsa_tgt=pla-1457925725188&hsa_kw=&hsa_mt=&hsa_net=adwords&hsa_ver=3&gclid=EAIaIQobChMIwZHvtaaG-wIVYQx9Ch2YeQEsEAQYAiABEgLmyPD_BwE

Edited by 11bravoZ71
Diamond817 Enthusiast

Diamond817

Posted
Posted
1 hour ago, 11bravoZ71 said:

 

 

I used the superchips tuner, part number 2847-S. Once you receive it in the mail you fill out a form online with instructions it was VERY easy to do. 
 

Then  I had to ship my  ECM to them to get it unlocked, it’s included in the price of the tuner to get it unlocked. I just had to pay to ship it to them…. they then ship it back really fast on their dime overnight. Then you can use that tuner. 

 
 

We’ll worth the investment If keeping the truck long term like I plan to. To disable that DFM with a permanent tune. If the motor still fails later from a lifter I’m rebuilding it with a DFM delete kit and will already have the tuned off portion done. 

 

https://www.holley.com/products/tuners_and_programmers/handheld_tuners/parts/2847-S?utm_term=&utm_campaign=Google+Shopping+-+SuperChips+-+Brand&utm_source=google&utm_medium=cpc&hsa_acc=7848552874&hsa_cam=13757689632&hsa_grp=125866783153&hsa_ad=531361842411&hsa_src=g&hsa_tgt=pla-1457925725188&hsa_kw=&hsa_mt=&hsa_net=adwords&hsa_ver=3&gclid=EAIaIQobChMIwZHvtaaG-wIVYQx9Ch2YeQEsEAQYAiABEgLmyPD_BwE

Thanks for the info. I didn't think the ECM's on these trucks could be unlocked. 

Snakes709 Enthusiast

Snakes709

Posted
Posted
On 10/12/2022 at 2:34 PM, 11bravoZ71 said:

Has anybody done a hard delete+tune off  on a DFM 5.3 or 6.2 

 

I see these guys made a kit recently… hopefully people start finding ways to do it,  to get data on longevity. 
 

https://www.michiganmotorsports.com/camshafts-michigan-motorsports/dod-afm-delete-kits/2019-l84-5-3-dfm-lifter-delete-kit-dod-afm-5-3l-gen-v-kit/

I know a local guy (alberta, canada) has done it as my buddy tuned his truck. No idea how its running though. 

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