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Which Programmers Allow Disable Of Afm/v4 Mode?

andymiller

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andymiller Enthusiast

andymiller

Posted
Posted

Thanks I have done a search, and didn't find any results that I was looking for.

 

I do realize I may lose MPG.

 

 

Now thats out of the way so people don't auto respond. Which tuners allow for deactivation on AFM mode?

 

 

thanks

slomo007 Enthusiast

slomo007

Posted
Posted

I just can't comprehend how it's mechanically possible to NOT lose MPG by turning it off. I realize people say it's useless....but think about it, if no fuel is being used in 4 cylinders for any amount of time, then fuel is being saved.

 

I am considering turning mine off this weekend when Justin is in town, but am nervous that I'm going to end up regretting it and having to mail the ECM back to him to turn it back on.

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted
I just can't comprehend how it's mechanically possible to NOT lose MPG by turning it off. I realize people say it's useless....but think about it, if no fuel is being used in 4 cylinders for any amount of time, then fuel is being saved.

 

I am considering turning mine off this weekend when Justin is in town, but am nervous that I'm going to end up regretting it and having to mail the ECM back to him to turn it back on.

 

The amount lost is negligible and unnoticeable. AFM is never activated above about 6% throttle (very little load). And when it is, the other 4 cyls are consuming more fuel (they are working harder).

 

You will NOT regret turning it off, trust me. I have ZERO regrets and I honestly did not notice one bit of MPG loss.

Stevens03 Senior Enthusiast

Stevens03

Posted
Posted
I just can't comprehend how it's mechanically possible to NOT lose MPG by turning it off. I realize people say it's useless....but think about it, if no fuel is being used in 4 cylinders for any amount of time, then fuel is being saved.

 

I am considering turning mine off this weekend when Justin is in town, but am nervous that I'm going to end up regretting it and having to mail the ECM back to him to turn it back on.

 

The amount lost is negligible and unnoticeable. AFM is never activated above about 6% throttle (very little load). And when it is, the other 4 cyls are consuming more fuel (they are working harder).

 

You will NOT regret turning it off, trust me. I have ZERO regrets and I honestly did not notice one bit of MPG loss.

 

 

What he said... I've got mine turned off with diablo. Zero loss of mileage. Checked it several times.

66nova Senior Enthusiast

66nova

Posted
Posted
I just can't comprehend how it's mechanically possible to NOT lose MPG by turning it off. I realize people say it's useless....but think about it, if no fuel is being used in 4 cylinders for any amount of time, then fuel is being saved.

 

I am considering turning mine off this weekend when Justin is in town, but am nervous that I'm going to end up regretting it and having to mail the ECM back to him to turn it back on.

 

 

I think it really depends mostly on your driving style. For me, I don't think I would see much difference 90+% of the time. I rarely drive a long enough distance to let the AFM kick in. It's stop, go, stop, wait on a train, go, wait on the same train because it is looping around, go, etc. I know there have been times when the AFM really has helped my mileage. There have been a couple trips when I drove 68-72mph and got 20-21mpg over a 2 hour trip.

Now, more often I drive 75+mph and the AFM rarely is on and I get 16-18mpg.

 

I have said this before, but AFM does not really bother me and I would not even consider turning it off IF I did not tow a trailer. It pisses me off when I am towing. Kick on, not enough power, kick off, kick on, off, you get the point.

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted
I just can't comprehend how it's mechanically possible to NOT lose MPG by turning it off. I realize people say it's useless....but think about it, if no fuel is being used in 4 cylinders for any amount of time, then fuel is being saved.

 

I am considering turning mine off this weekend when Justin is in town, but am nervous that I'm going to end up regretting it and having to mail the ECM back to him to turn it back on.

 

 

I think it really depends mostly on your driving style. For me, I don't think I would see much difference 90+% of the time. I rarely drive a long enough distance to let the AFM kick in. It's stop, go, stop, wait on a train, go, wait on the same train because it is looping around, go, etc. I know there have been times when the AFM really has helped my mileage. There have been a couple trips when I drove 68-72mph and got 20-21mpg over a 2 hour trip.

Now, more often I drive 75+mph and the AFM rarely is on and I get 16-18mpg.

 

I have said this before, but AFM does not really bother me and I would not even consider turning it off IF I did not tow a trailer. It pisses me off when I am towing. Kick on, not enough power, kick off, kick on, off, you get the point.

 

 

Mine NEVER, EVER activated above 65 MPH (unless I was decelerating). And on a level freeway, at 60 MPH, with a tailwind, i could get it to activate, but turninging on the A/C kicked it off. :thumbs:

 

AFM = Lame!

 

VVT saves far more fuel than AFM could ever dream of.

andymiller Enthusiast

andymiller

Posted
  • Author
Posted

Thanks fellers for not blasting the crap out of me. I'm at work and trying not to stay on here long. Can anyone give me part/model numbers.

 

I'm trying to buy one for my brothers B-day as quick as I can

jdg2 Enthusiast

jdg2

Posted
Posted

AFM :thumbs: I had my AFM turned off and took a trip from Silver Spring, MD to North Carolina's Outer Banks and averaged 17.5 mpg. That was with 3 people in the truck, loaded from the front of the bed to the back, top to bottom under the cap and AC on the whole way, running 65 to 80 (mostly 70-75). The best road trip mileage I ever got before turning AFM off was 17.7 and I didn't have as much of a load in the truck then(I wouldn't consider that a loss of mpg). The truck just seems to run so much smoother with it off. I know I am glad it's off ,I don't miss it and no regrets. Just my 2 cents worth..

andymiller Enthusiast

andymiller

Posted
  • Author
Posted

Thanks for all the responses. Are there any programmers that allow you to control the function of Traction Control and Stablitrac as well??

ShoddyHog Enthusiast

ShoddyHog

Posted
Posted

If you really want to go nuts and be able to control EVERYTHING and log EVERYTHING, get HP Tuners. You'll need a laptop though...and some computer skillz :thumbs:

 

With HP Tuners, I could see when AFM was kicking in and out, and couldn't feel a thing. I still disabled it, and it will remain disabled because of what Jeff said. In addition to the incredibly small amount of throttle that would cut it off, my DFCO (Deceleration Fuel Cutoff) never, ever enabled while AFM was enabled.

 

I haven't run enough tanks through to give you a personal opinion on the MPG, but it appears as though everyone is right. In the couple tanks I've run though, there was very little difference as in less than one MPG.

 

Gerry

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