08 3.9 with Active Fuel Management

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Is there any way to disable the fuel management in an 08 impala? It has 111k, great gas mileage, uses next to no oil but I'm just not a fan. Anyone have testimony on something that works without tearing into the engine?
 
I believe the Range Technology AFM disabler works with the 2008-2009 Impala 3.9. It plugs into the OBD2 port. Most companies that make generic handheld tuners (Diablosport, Superchips) only make tunes for the Impala SS 5.3. It's also possible to deactivate AFM with a custom tune with software like HPTuners. Any local tuner that specializes in GM tunes should be able to help.
 
Pro-cal or flash-cal should work, use pro-cal to disable DRL on my Jeep for new led halos, but I know one of the options for rams was to disable AFM I believe.
 
The Range Technology Disabler will work. They're $200 to buy new... I bought one for the GMC in my signature used for $80 from a guy who sold his Chevy. Keep an eye out.
 
Did you see a drop in mpg? I got around 28.5 on a thousand mile trip and enjoyed that part of it. Any issue long term by disabling it?
 
Superchips tuners can disable it, contrary to what others say. Speaking from experience. Had a Superchips Cortex 2950 for my 2008 Impala SS LS4. Best purchase I ever made. Not sure if they're compatible with the 3.9L though. Range will also disable it.

In my case with the 5.3L, my mpgs went UP running 8 cylinders full-time. This was tracked over 6 years. I had excessive oil consumption too. 1 quart every 750 miles. Immediately after the tuner, consumption went to zero. Didn't lose a drop for years after, including the day I sold it.

Just be aware that unless you *physically* remove the AFM components, they can still fail, even if they're never in use. So please maintain it still. Not sure if the 3.9L has a "Valve Lifter Oil Filter" like the LS4, but that little filter is crucial to AFM health.

Good luck, they're great cars minus AFM, the air door actuators, and the delicate 4T65. Which reminds me, when was your last trans fluid service?
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Originally Posted by alchargo
I believe the Range Technology AFM disabler works with the 2008-2009 Impala 3.9. It plugs into the OBD2 port. Most companies that make generic handheld tuners (Diablosport, Superchips) only make tunes for the Impala SS 5.3. It's also possible to deactivate AFM with a custom tune with software like HPTuners. Any local tuner that specializes in GM tunes should be able to help.
I misread what you said. My bad. I thought you said Superchips/Diablo didn't disable AFM. So yes. You may be correct that they don't make one for the 3.9L.
 
I serviced the tranny the day I bought it @109k. Son in laws brother is a GM tech. According to him he seen very little problems with the 3.9 compared to the v8 version. It works pretty seamlessly but I just can stand the faint shudder when cruising. And I have no idea what lifter filter your talking about.
 
Originally Posted by D1dad
I serviced the tranny the day I bought it @109k. Son in laws brother is a GM tech. According to him he seen very little problems with the 3.9 compared to the v8 version. It works pretty seamlessly but I just can stand the faint shudder when cruising. And I have no idea what lifter filter your talking about.

Yes, when comparing the V8s, the V6 models look amazing, but the 4T65 still fails more than most think, even with perfect maintenance. Not trying to say it'll break tomorrow, just saying take care of it. As for the filter, Google what's in quotations and add "LS4", you'll see.
 
At $200.....Range Technology AFM disabler is a JOKE!!


HP-Tuners dongle & software is $300, Specific vehicle credit is $100. Not only can you disable the AFM....You can change/edit thousands of other things in the calibration & it includes a bi-directional scan tool.
 
I found a local guy who comes highly recommended and will disable it via tune for $100. So far that seems like the better option over a plug and play Disabler.
 
Originally Posted by clinebarger
At $200.....Range Technology AFM disabler is a JOKE!!


HP-Tuners dongle & software is $300, Specific vehicle credit is $100. Not only can you disable the AFM....You can change/edit thousands of other things in the calibration & it includes a bi-directional scan tool.


I went to the site and can make no sense what so ever of what I would need or how to use it.
 
You will need a Laptop PC, You download the software & drivers for the Editor & Scanner, Editor & Scanner are separate programs.

The Dongle & the rights to buy Editor credits is what your physically paying for.

You can scan & data log all you want for free, To edit a ECM calibration via the Editor.....You have to licence that controller. Yours will take 2 credits at $50 per, This will licence the Engine & Transmission controllers for life. (Fuel Pump Control Modules are 1 extra credit) But you don't have to licence that module.

They will not advertise the capability of this tool for obvious reasons!
 
I got the afm shut off yesterday by a guy from Ft Wayne indiana who does mail your pcm tunes, I was close enough to drive there. $105 and it was done. Great place with years of experience who I'd highly recommend. No more alternator chirp, exhaust drone and annoying surge. It was 50 miles away and really couldn't open it up for fuel mileage, but at 65mph I averaged 34 mpg so I don't think I'll see much of a fuel drop. My car uses next to no oil @ 114k so hopefully I staved off future issues. Now I have an actual 3.9 with no silly engineering which imo wasn't needed to begin with.
 
What software did they use? Good price regardless.

Keep in mind that if the ECM is ever overwritten with a stock/updated calibration....Your AFM will become active again.
 
No clue what software. I got the name from a Chevy site , he had done many of the 5.3 and 3.9 for its members and no issues to note of the software coming back on years later. Most folks removed their computers and mailed them in, I was lucky enough to live an hour away so if that happens, which he made no mention, I can take it back. All I know is he downloaded a copy of my current program in case I wanted to go back to afm, then went in and disabled it. Also was able to tell me that I have a low battery in a tire sensor and which one so that answers the tpms light issues. The guys pretty well known and reputable for custom tunes and has a ton of work so hope all ends well.
 
I meant.....IF you ever needed a software update to correct another issue even if it's not related to the AFM.....The entire calibration gets overwritten.
 
Yeah that's what he said when I asked him yesterday. The only way is if the dealer reprograms it and if so then he'd shut it off again for free.
 
Well at least I don't have a surging car at cruising speeds and the annoying exhaust drone. The car didn't really use oil so that wasn't the issue. Mpg seems to be about the same so I'd say it's a win win. Sorry but this is just something that gm didn't need to do on a pushrod engine that got great mileage to begin with.
 
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