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Afm V4 Mode Toggle Switch

camaroguy94

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camaroguy94 Enthusiast

camaroguy94

Posted
Posted

So I was just thinking has anyone ever though installing a toggle switch to keep the truck in V4 Mode. I dont need all that power all the time. I know it this probally will cause a ton of issues but just thinking out loud.

 

How much better MPG could I get???

georgecdisc Enthusiast

georgecdisc

Posted
Posted
So I was just thinking has anyone ever though installing a toggle switch to keep the truck in V4 Mode. I dont need all that power all the time. I know it this probally will cause a ton of issues but just thinking out loud.

 

How much better MPG could I get???

AFM is programmed into the ECM. There is no way to have a toggle switch for it. If you were to run V4 all the time, it would probably get worse gas mileage as you are trying to move a heavy vehicle on half the power. At times it is more efficient to use 8 than make the 4 cylinders struggle to provide enough power.

cerbomark Senior Enthusiast

cerbomark

Posted
Posted

I don t believe that engine is made to run that way and I bet you d do major damage. That s why it s programed with limits of how long it will run in that mode.

Anf IF you could or did you d get great gas mileage while your taking a bus :rolleyes:

brims Senior Enthusiast

brims

Posted
Posted

I toggled mine to full time V8. Technically Justin did, but minor details. I've seen no difference in gas mileage since doing that. Trucks shouldn't have 4 bangers, part time or otherwise.

Sir Dan Enthusiast

Sir Dan

Posted
Posted
I toggled mine to full time V8. Technically Justin did, but minor details. I've seen no difference in gas mileage since doing that. Trucks shouldn't have 4 bangers, part time or otherwise.

+1 !!!

Very minimal increase in mileage and just in city if any at all. It's a great technology for cars, but NOT trucks. :rolleyes:

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted
I toggled mine to full time V8. Technically Justin did, but minor details. I've seen no difference in gas mileage since doing that. Trucks shouldn't have 4 bangers, part time or otherwise.

+1 !!!

Very minimal increase in mileage and just in city if any at all. It's a great technology for cars, but NOT trucks. :confused:

 

 

What they said! :rolleyes:

07SLT Enthusiast

07SLT

Posted
Posted

So I'll retain the 19-20 mpg (highway) that I get now after turing my afm off? Sorry, I'm sceptical.

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted
So I'll retain the 19-20 mpg (highway) that I get now after turing my afm off? Sorry, I'm sceptical.

 

Obviously everybody's results will vary.

 

But my truck NEVER went into V4 mode above 65 MPH. I drive mostly city/inter-city freeway. And when I do get on the freeway, I never drive less than 65 MPH. It also never stayed in V4 mode unless the freeway was flat/downhill and my speed was 60 MPH or less. One time, as a test, I set the cruise at 55 MPH and waited for a flat section of freeway. The AFM came on, I turned on the AC and it went to V8 mode. :rolleyes: And this was before my leveling kit and wheels/tires.

 

Yes, if drive slow enough on flat hwys, I suppose AFM might net you 1-2 MPG increase.

 

In my case, I have seen ZERO dropoff in my MPG since shutting it off.

 

I still say a 8/6 AFM system would have made much more sense in these huge trucks.

Silverado4x4 Senior Enthusiast

Silverado4x4

Posted
Posted
So I was just thinking has anyone ever though installing a toggle switch to keep the truck in V4 Mode. I dont need all that power all the time. I know it this probally will cause a ton of issues but just thinking out loud.

 

How much better MPG could I get???

The system is designed to run in 4 mode for a max of I think 7 minutes if nothing is there to kick it out, the reason is for keeping the even heat transfer inbetween cylinders.

Nick The Great Senior Enthusiast

Nick The Great

Posted
Posted

I wouldn't see why a toggle switch couldn't be added. It'd probably take some relays, signal conditioners, logic gates, and a good understanding of EFI live or whatever. I seem to recall Justin was adjusting stuff on the fly during my tune. Not AFM, but shift points and such.

 

Maybe it's not a good idea, but it sounds like a fun project to me. :rolleyes: I think it'd be fun to have a bunch of little dials to adjust your shift points, and other parameters. :confused:

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted
I wouldn't see why a toggle switch couldn't be added. It'd probably take some relays, signal conditioners, logic gates, and a good understanding of EFI live or whatever. I seem to recall Justin was adjusting stuff on the fly during my tune. Not AFM, but shift points and such.

 

Maybe it's not a good idea, but it sounds like a fun project to me. :rolleyes: I think it'd be fun to have a bunch of little dials to adjust your shift points, and other parameters. :M16:

 

Shut up Nerd! :confused:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

:mad:

iminaquagmire Enthusiast

iminaquagmire

Posted
Posted

Its also designed to switch back to 8 cylinders if the the throttle exceeds 6% IIRC. If you equate that to HP, that's 18.5 HP. Anytime your truck needs more power than a lawn tractor, it switches pack to 8 cylinders..

DofD Senior Enthusiast

DofD

Posted
Posted

When I get around to getting a tune done (there are other priorities), I'll get AFM turned off. The terrain around here is just too hilly (city or highway) for AFM to be of any benefit. AFM only comes on for a few seconds if I'm on flat ground going a constant speed or going downhill. Maybe in an hour of driving I might get 1 minute in V4 mode.

gmowner4life Enthusiast

gmowner4life

Posted
Posted

You would probably get worse gas mileage because of the amount of power you would need to get momentum. The weight to power ratio would not let you have any gains in mileage. :rolleyes:

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