Afm

[Art708]

Does driving the car in Manual mode deactivate AFM? I was riding slowly in town and keep feeling it drop into AFM. I shifted over to manual and it seemed to not change ....didn't feel the vibration or hear the drone.

[GRRRR8]

No. It will even activate in M4 cruising.

[Art708]

That bites. There should be a way we could turn it off and on when we wanted to. Engineering mode should have that function.

[GRRRR8]

I would think they would have it that way also.

[jnak]

Is there any reason why you would want it off?

[GRRRR8]

It is unnecessary for it to activate in manual mode and the constant on and off is not any better for fuel economy.

[jnak]

But is it actually doing any harm by having it active? Does it increase engine wear, hurt performance, make your balls itch, etc? Because if it doesn't hurt anything, then why does it matter if it's on or not?

[GRRRR8]

I dont think we know if it is harming anything YET. I hate that if I am in M3 or M4 and I want to act 18 years old that I all of a sudden it turns into John Boy on a John Deere. Its not real good for the intimidation factor! Thats why all that crap is becoming paper weights real soon. Those lifters are not going to take the abuse of the standard lifters anyways.

[Art708]

Do you think there'd be any benefit from turning it off via a tune......or is that possible? I wonder how much gas mileage would suffer on the highway.

[-Ray-]

G8Smitty had his turned off. As long as I keep make 300 miles plus trips in my G8, I'm keeping it.

[locrzn#92]

I always run mine in manual mode anymore. The new mufflers give off the drone and I hate it. My mileage is almost indentical as in the drive mode. I've was getting about 21.9 or so in the drive mode before I put the mufflers on and now in the manual mode in 6th gear on the highway I still get 21.5. Honestly I not worried about 1/2 mpg on any trip. You don't get any of that drone shit in manual mode at all. Its very enjoyable to drive on the highway or anywhere for that fact. I know what the DOD is, but, what does the AMF mean?

[-Ray-]

Active fuel management.
I'm getting over 27 mpg on the interstate. Last time it was 30.1 over 350 miles.

[locrzn#92]

WTF Ray, wheres that over 5 mpg coming from, the tune or are you driving 10 mph the whole way? I usually run about 76-77 mph. My rpms are just under 2000 rpm. I've heard others talk about how bad there mpg is and then other how good theirs is. These cars shouldn't vary more then a couple mpg. I know the altitudes, temp and humidity as well as how flat or how hilly it is. If mine would get 25-27 mpg I would get a tune today. I did find a place in KC MO that can tune my car with EFI LIVE, they have a place called House of BOOST. They are currently building a twin turbo g8. All the guys who work and own the place worked at ProCharger and now have their own shop. So, I may head up there in a couple weeks to get it done. They do a lot of SSTrailblazers and LSx motors.

[GXPaycheck]

I would love to know how you are doing it. I can't get mine over 25. Got 26.7 once, and 29 once on different highway trips using different ecm's (max of 23.5 stock) but have not been able to duplicate the feat.

[-Ray-]

It takes effort to get that kinda mileage. First off, I use my G8 as my work car. I travel mostly to Ohio from North of Indy. I use the best 93 octane I can find. No ethanol.
I try to keep my AFM active the whole time I'm driving. On hills I gain speed as I go down to try and make a run up the next one. Thankfully the mid-west dosn't have a lot of hills.
I run around 72 mph. Speed limit in Ohio is 65. I've passed many a trooper at that speed and never had a problem, while people with Ohio plates are hitting their brakes.

[GXPaycheck]

Ray, you use the VMS tune, right?

[Art708]

I always run mine in manual mode anymore. The new mufflers give off the drone and I hate it. My mileage is almost indentical as in the drive mode. I've was getting about 21.9 or so in the drive mode before I put the mufflers on and now in the manual mode in 6th gear on the highway I still get 21.5. Honestly I not worried about 1/2 mpg on any trip. You don't get any of that drone shit in manual mode at all. Its very enjoyable to drive on the highway or anywhere for that fact. I know what the DOD is, but, what does the AMF mean?

AFM- DOD....same thing, right?

[-Ray-]

Ray, you use the VMS tune, right?

Yes.
AFM= Active fuel management
DOD= Dept. Of Defense...I mean Displacement on Demand.

[edmanet]

Do you think there'd be any benefit from turning it off via a tune......or is that possible? I wonder how much gas mileage would suffer on the highway.


I'll let you know in a couple of weeks about mpg. I had that shit...I mean AFM turned off when VMS did my tune the other day. If I'm lucky I'll get to drive the bitch tomorrow.

AFM is annoying as hell. If you want a gas sipper buy a Prius...this is a performance car. Who cares about mpgs.

[-Ray-]

Thursday on my way back from Cleveland I got 28.7 mpg. Previous trip was 30.1. I had a strong headwind when I headed West this time though.
A 29.4 mpg avg. over 2 trips is not bad.

[Need4spd]

No. It will even activate in M4 cruising.GRRRR8, are you sure it activates in in manual mode?

I have never been able to get it to go into 4cyl mode when in manual mode.

It does in sport mode and standard, but I have never seen it go to 4cyl in manual. I have seen others report this also.

Thanks,

[GRRRR8]

All the time. It is not instantly, but once a cruise speed has been established it goes into AFM.