Loosing more and more MPG!!

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retiredsparky

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Brandon, I didn't see in this thread anybody talking about AFM delete.

It is a great mod, since it eliminates an expensive repair down the road.

But, there is a cost in fuel economy, which can be 1-2 mpg, depending on city/hwy driving percentage. That AFM system will constantly switch between 8 and 4 cylinders. The newest version controls even more cylinders (A GM solution to a crappy solution-make it worse).

I would rather pay for fuel than repairing the engine.

Also, in the future, you could experience a failure in the sensor that detects level of alcohol in the fuel. It is not an uncommon failure.
 

retiredsparky

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One more thought on AFM --Koenigsegg has produced engines for some of their high end cars that don't use a cam. they have computer controlled valves. A reduction in engine weight, increase in efficiency and power. They also designed a 4 cylinder engine for a major Chinese car manufacturer using the same technology. So hopefully, someday, that technology will migrate into vehicles in our country.
 
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Jolly Roger

Jolly Roger

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Brandon, I didn't see in this thread anybody talking about AFM delete.

It is a great mod, since it eliminates an expensive repair down the road.

But, there is a cost in fuel economy, which can be 1-2 mpg, depending on city/hwy driving percentage. That AFM system will constantly switch between 8 and 4 cylinders. The newest version controls even more cylinders (A GM solution to a crappy solution-make it worse).

I would rather pay for fuel than repairing the engine.

Also, in the future, you could experience a failure in the sensor that detects level of alcohol in the fuel. It is not an uncommon failure.

Thank you retiredsparky! I have turned my AFM off by the use of a Superchips flashcal. Its not a tuner, just a simple re-calibration tool for the speedometer for when you add larger tires. I bought it because it had the AFM options on it and was also hoping at the time it had some TPMS settings which it did not. It does have a code reader/clearing ability.

I never saw a reduction in MPG after turning off AFM. Many here have claimed the same and even boasted improved MPG.
Before I take it in for any servicing or where there is a chance of someone plugging into my OBDII port, Im sure to uninstall back to its stock configuration. Ive heard to many horror stories about vehicles becoming "bricked" and having to be towed to the dealership.

I wasn't aware that my year tahoe had a sensor that detected the level of alcohol in the fuel. I remember reading somewhere that particular "alcohol sensor" type of system was problematic and that is why they switched to a "sampling calculation" system instead?
 
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Jolly Roger

Jolly Roger

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This also raises a question with my new Bluetooth OBDII adapter tool that I have coming.
I run the Superchips tool and turn off my AFM. I unplug the Superchips and store it away until its time for someone to service the truck.

Am I going to be able to plug in and run the new Bluetooth OBDII tool while I have the Superchips changes installed at the same time?
..or should I uninstall all the options I have with the Superchips before plugging in and running the new Bluetooth OBDII tool?

The only things I change with the Superchips is turning off AFM, turning off speed limiter, and change tire size so the speedometer is correct.

https://superchips.com/shop/gm-flashcal-for-truck
 
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