DFM disabler released

[jfoj]

Will watch the Evap Monitor on my truck, I have had a lot of starts and driven quite a few miles since I last triggered codes when installing and testing my Park Release cable and then clearing codes. Maybe it has been too cold for the Evap to clear, as I recall temperature does play into the Evap testing due to expansion and contraction of the fuel.

But even before the Polar Vortex hit my area, I would have expected the Evap to clear if it as going to. Who knows, but it was interesting the reply from Range unless this was just their "canned" reply, remove the device and run Drive Cycles. Maybe their device delays the Readiness Monitors turning to Ready. So beware and check before an Emission Inspection.

I would prefer not have to remove it, just extra work.

 

[jfoj]

Wanted to post a follow up.

My Evap Readiness Monitor finally cleared with the Range module in the vehicle.

From my experience it seems with the Range module certain Readiness Monitors may take longer to change their state to Ready than without the module.

Kind of disappointed that the Range staff even stated that the module would need to be removed and the Emission Drive Cycle would need to be performed until the Readiness Monitors were set to Ready.

I think this was either someone at Range that did not understand how their device functioned or just figured it was quicker and easier to tell people to remove the module to get the vehicle ready for Emission Testing if the Readiness Monitors were not all set to Pass/Ready/Clearf.

So a word to the wise, anyone with a Range device should check the Readiness Monitors on their vehicle a few weeks prior to Emission Testing to be 100% sure the vehicles Readiness Monitors are all in a Pass/Ready/Clear state.

Overall I have no complaints about the Range device at this point in time. While the Cylinder Deactivation Counters DO increment on Decel with Fuel Cutoff as monitored on a more advanced scan tool. I have not 100% verifiied if the DFM solenoids are active during DCO at this point. Even if the DFM solenoids are active and the lifters are collapsing, during DCO, I still see this as a win as there is far less activity with the lifters collapsing during DCO then if the entire system was left active.

 

[jerry455]

I am looking to purchase a scan tool. I work for GM but will be retiring while I still own my truck and won't have access to an MDI 2. What tool do you have?

 

[jfoj]

I am looking to purchase a scan tool. I work for GM but will be retiring while I still own my truck and won't have access to an MDI 2. What tool do you have?

So this is somewhat a loaded question. I often base scan tool choice on what the tool could save me in repairs to how much I would pay for the tool. If you do most of your own repairs and can troubleshoot well and are not afraid of electrical systems, then maybe invenst more in a tool. If you use a shop for most of your work, but want a chance and maybe repairing things yourself or at least having an idea how critical a problem is, a lower to mid priced tool is for you. Also if you have household of different vehicle brands, you may need to spend more, i.e. if you have GM, Toyota and a BMW, you may need a tool that supports those brands rather than a more specific US or GM tool.

I recommend EVERYONE that has an ounce of technical knowlege have at least a plain, generic OBDII tool for reading and clearing codes. One of the cheapest and I think best bang for the buck is the OBDFusion App which has a version for both Android and Apple IOS. $10 for the App tops and about $30-$40 for a wireless interface to work with the App. If anyone wants suggestions on an interface, message me and I will make some recommendations. Keep the interface in the console or glovebox of all your vehicles and you ALWAYS have an OBDII tool on hand for your vehicle or helping out family of friends.

You really need to understand what you really need, many people try to over buy on a tool as well.

I break tools into a few categories:

A. Level 1 - Basic generic OBDII tool, works with almost anything from 1996 up and assists with the MAJORITY of things that trigger the SES/CEL/MIL. Everyone needs one of these. OBDFusion is my go to App and has been for over 10 years.

B. Level 2 - Supports generic OBDII and typically adds things like ABS and Airbag codes and clearing error support. These can be cheaper asian tools for typically between $75-$200. Some have lifetime, updates, some you pay for updates.

C. Level 3 - A slightly more advanced tool that may support some bi-directional control for testings and trouble shooting, may support TPMS, Electronic Parking Break, ABS Brake Bleeding, Battery Registration on vehicles that require it, Clearing Service Reminders and might support other modules as well. Some may have add on modules for battery and chargings system tesing and even borescope cameras. These tend to be in the $400-$700 range depending on vendor and module support.

D. Then there is the class of tools that probably start around $1000 and range up to price to $5000 and have expensive updates. These tools tend to support more bi-directional control, module programming, key programming, and more. These tools may also support Collision Avoidance Sensors, Parking Sensors, Cameras and more. They also have a bit more learning curve as well. Some of these may be OE tools or OE tool clones.

I recommend everyone have more than 1 tool.

Have a Level 1 OBDII App on their phone/tablet and a wireless interface. This is a bare minimum.

Then depending ones skill level, they should have at least a Level 2 or Level 3 tool. Prices are higher for a Level 3 tool, but if you can save a single shop trip for something a bit more complicated by having a Level 3 tool, it may pay for itself on the first use.

I have too many scan tools. Some are a bit outdated due to the cost of updates, some are somewhat obsolete for the newer cars, but are very advanced for older cars.

I would say the Autel or Launch tools have a good price to feature set. Are pretty easy to use and update. Many of these tools are now effectively Android based tablets with Wifi and Bluetooth. Many can update over Wifi now, so no need to connect to a computer or pull a memory card and update with a computer. Some have wireless OBD interfaces so you are not tethered in the drivers seat. Autel usually charges around $250 for annual updates, I usually only update my tools every 3-4 years unless I really need a more current update. Some Launch tools have free updates.

There are a number of tools around the $500 range that give additional info like oil pressure, oil temperature, will show DFM activity, show what gear the transmission is in, most can graph sensors as seem from the ECM on the tool. While on tool graphing can be useful, I often find for more complex issues having a tool that can aquire data and be exported can be more useful.

Believe it or not OBDFusion has this ability for the basic OBDII sensors, but not what are typcially considered Extended PID's. OBDFusion does have some add on packs for different models, but unfortunately no GM due to the way GM's licensing works, it is far too expensive for a smaller company with low cost Apps to have GM specific data available.

Anyway, this is a broad subject that could use its own forum. Anyone that has specific quesitons, message me and I can hopefully give some recommendations.

 

[jerry455]

I have my own Tech 2. I loved using that. I wish GM wouldn't have gone the MDI and computer direction. It is so much easier with a stand alone tool. I have always repaired my own vehicles. So I would like to buy a good scan tool that can diagnose all of the systems on the truck. I have never even used the "free" oil changes when my vehicles were new. I prefer to do all of the maintenance myself.

 

[jerry455]

Maybe there could be a thread on what scanners people have and how they use them, just read codes or more in depth.

 

[jfoj]

I have my own Tech 2. I loved using that. I wish GM wouldn't have gone the MDI and computer direction. It is so much easier with a stand alone tool. I have always repaired my own vehicles. So I would like to buy a good scan tool that can diagnose all of the systems on the truck. I have never even used the "free" oil changes when my vehicles were new. I prefer to do all of the maintenance myself.

I am with you on your concern. Most manufacturers for the dealer service depts have gone the way of computers becasue these vehicles have so many computer modules and software updates and module programming to the vehicles need to be performed.

You can still use stand alone tools, they will have their limits, but if a module needs coding or software updates are needed, this is best to send to the dealer anyway due to some of the 3rd party tools not playing well and you need to get the software files which is not always easy.

 

[PPV_2018]

just for what it’s worth, i guess this is a good place to put this, but i have the range obdII unit, and the other night i was in the drive thru. I noticed the when i let off the brakes there was a more intense glow so i started paying attention, and when the brakes were applied and the vehicle was not moving there was only 1 led lit. When i let my foot off the brake, all led’s were lit.

Not sure if anyone else has noticed this. i guess this implies unit Is not active during idle (either because afm is not activated or other reasons)

 

[Antonm]

I think maybe you’re in the wrong section. AFIK range does not make an OBD2 port device for the 21 and up models.
What year is your truck?
…

 

[PPV_2018]

Yeah you are right on all accounts. . . my truck is a k2 , but tbh I just didn’t know where to put this and didn’t want to make a new thread to show off my feet lmao

I figured that the overall operation of the modules may be similar or the same to the t1’s, so it may lead some insight across the board.. i could be wrong considering afm and dfm are different so yeah this might be totally irrelevant

 

[seatown]

Sorry to pop in here and deviate a little. We’re going to test drive some 21, 22 tahoes and Yukons this weekend… all 5.3. What should I be asking? Getting suspicious these were traded cause someone knew they had bad drivetrains.
Is there a way to know if it has the engine with the bad supplier parts?

 

[Silverado4x4]

Sorry to pop in here and deviate a little. We’re going to test drive some 21, 22 tahoes and Yukons this weekend… all 5.3. What should I be asking? Getting suspicious these were traded cause someone knew they had bad drivetrains.
Is there a way to know if it has the engine with the bad supplier parts?

They identified the bad supplier parts in the 5.3 motors from Sept 1 2020 to March 31 2021 engine build date not vehicle build date. On the 2021 Tahoe and Yukon I would probably stay away from that one unless it was already repaired or outside the engine build date. When the vehicle is built lets say in May the engine was probably built 1-2 months before that it's a question to ask the selling dealer if the repairs were made on the 2021.

 

[seatown]

This is a long shot. But someone really knowledgeable about the part numbers and packages willing to look at a dealer packet about one the vehicles I am looking at?

 

[nick14226]

This is a long shot. But someone really knowledgeable about the part numbers and packages willing to look at a dealer packet about one the vehicles I am looking at?

Carfax will show the repairs I’d imagine too, and most dealers will/should provide.

 

[seatown]

Carfax will show the repairs I’d imagine too, and most dealers will/should provide.

alright…
So clue me in here.
I went and looked at 3 Tahoes today. All 2021, but different trim.
Here is one of them
2021 z71
I assume all three the exact same drivetrain train. And from reading here I think that is the L84 with 10speed?

1) it has dfm, is there a specific recall or repair I can ask if they’ve done?
2) from my understanding the “certified pre owned”, warranties the drive train up to 100k miles?
3) back to this thread, is this disabler almost a must have? So plan for that too?

 

[seatown]

They identified the bad supplier parts in the 5.3 motors from Sept 1 2020 to March 31 2021 engine build date not vehicle build date. On the 2021 Tahoe and Yukon I would probably stay away from that one unless it was already repaired or outside the engine build date. When the vehicle is built lets say in May the engine was probably built 1-2 months before that it's a question to ask the selling dealer if the repairs were made on the 2021.

Where do you find that date info? Sticker? Carfax?

 

[Silverado4x4]

Where do you find that date info? Sticker? Carfax?

 

[seatown]

View attachment 450311

Thank you very much… the rig I am interested in is definitely in that range.

 

[15burban]

) from my understanding the “certified pre owned”, warranties the drive train up to 100k miles?

From my understanding, which I could be wrong, but it says 6 years 100k from New vehicle delivery. So, from my understanding that 6 years starts from when Joe shmo bought it brand new. So basically there's only 2 years left of it and possibly only 1 year since it's a 21 and could have been bought at the end of 20. Ok so maybe more then a year and a half.

 

[seatown]

From my understanding, which I could be wrong, but it says 6 years 100k from New vehicle delivery. So, from my understanding that 6 years starts from when Joe shmo bought it brand new. So basically there's only 2 years left of it and possibly only 1 year since it's a 21 and could have been bought at the end of 20. Ok so maybe more than a year and a half.

That’s a very good point it is six year OR 100,000…. Original title purchase date 4/21/2021

This dealer has kind of avoided technical questions. I asked if they’d disable DFM… they gave me the “GM designed it this way” ok sure. And They highly suggested I don’t use 3rd party disabler ok sure.

Still a chance that engine has faulty parts due to above graphic.