Jump to content

2014+ AFM (Active Fuel Management)

Ron.s

By Ron.s
in Engines & Drivetrain

 Share

Recommended Posts

3tspapat Enthusiast

3tspapat

Posted
Posted

I've been driving in L7 unless I get on the highway, only then will I shift to L8 so AFM can take over. Also in L auto start/stop won't kick in.

 

I have a few tanks logged with this style and with the colder temps. Will drive the next tank in "D" with AFM and start stop and see how much of a difference that makes.

  • Thanks 1
  • Replies 555
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

oldmann
oldmann

Why are people so concerned about this topic. I do not understand it. Just drive it. End of story. And yes, even if you can't figure out why the truck has it, it is to save fuel.

pm26
pm26

No, it does not. Not even close. The only Cadillacs that possibly exceeded the weight of 2014 GM crew cab 1500 4x4 pickups were the old land yachts (1976 and older) models. I believe that a 1976 Ca

seamonster
seamonster

Whats up with the name calling?   Cant you see we agree----the AFM feels like a gear shift!   Many people want 6 and 8 speed tranny and then complain they can feel AFM. That is what I dont unders

Posted Images

UGAuChev17 Enthusiast

UGAuChev17

Posted
Posted

My guess is negligible. I have 20K on my truck. Half with AFM and half with AFM deleted. My mileage is the same without it and I added a CAI, exhaust and tune, which only gives me a little more of a lead foot.


Sent from my iPhone using Tapatalk

UGAuChev17 Enthusiast

UGAuChev17

Posted
Posted

My guess is negligible. I have 20K on my truck. Half with AFM and half with AFM deleted. My mileage is the same without it and I added a CAI, exhaust and tune, which only gives me a little more of a lead foot.


Sent from my iPhone using Tapatalk

3tspapat Enthusiast

3tspapat

Posted
Posted (edited)

Logged my morning work commute the past 2 days with same route (10 miles one way), traffic, driving and environmental conditions. It's city driving but about 1/3 of the way the limit is 60 MPH. Max speed is 60 MPH, average is 24 MPH. Driving style is for gas economy (Shifts mostly at 2000 RPM, never exceeding 2500 RPM). 

  1. 1/28/19 - air temp 55 - Driving in L7 mode so start/stop and AFM disabled - 15.1 MPG
  2. 1/29/19 - air temp 55 - Driving in L8 mode so start/stop disabled and AFM active - 19.1 MPG
  3. 1/29/19 - air temp 72 -Driving in D with start/stop and AFM active - 23.0 MPG
  4. 1/30/19 - air temp 58 - Driving in D with both start/stop and AFM active - 21.5 MPG

Also noted decreases in AAPM, FPM, SCPM and MFPM for my vehicle but increased values for other commuters

Edited by 3tspapat
F4Gary Enthusiast

F4Gary

Posted
Posted
On 1/23/2019 at 11:56 PM, joshuaandrew14 said:

I feel the AFM switch from V4 to V8 every time it does it. Also, I'd imagine it's because of AFM, but my truck has kind of a rough idle and smells like it runs rich! WTF?

I don't believe this for a second.  You can hear V4 mode, but you can't feel it go in and out.

KARNUT Senior Enthusiast

KARNUT

Posted
Posted

You hear it in the exhaust. My brother in laws Ram, the only way you know it's in V-4 is the dash light and exhaust sound, My GMC was the same way


Sent from my iPad using Tapatalk

SS502 Senior Enthusiast

SS502

Posted
Posted

I can't feel it (although I am rarely in Drive, usually L7) but I can hear it with the Borla ATAK...with the stock exhaust, I could not even tell without seeing the indicator in the cluster.

joshuaandrew14 Enthusiast

joshuaandrew14

Posted
Posted
I don't believe this for a second.  You can hear V4 mode, but you can't feel it go in and out.


Do you want to come drive my truck? It’s noticeable every time. Why would I lie to guys on a forum about this? Lol.


Sent from my iPhone using Tapatalk
KARNUT Senior Enthusiast

KARNUT

Posted
Posted

Some you can feel, my daughters Honda you can feel the switch. My father in laws you can't . The exhaust quiet you don't hear it. Louder exhaust you'll hear it.


Sent from my iPad using Tapatalk

SS502 Senior Enthusiast

SS502

Posted
Posted
1 hour ago, joshuaandrew14 said:

 


Do you want to come drive my truck? It’s noticeable every time. Why would I lie to guys on a forum about this? Lol.


Sent from my iPhone using Tapatalk

 

I believe you and was just relaying my truck’s tendency’s ? but I’d love to drive your truck ?

  • Like 1
3tspapat Enthusiast

3tspapat

Posted
Posted

My wife always says she can feel it going in and out....HAAHHAAH

No i'm not off topic...

I can actually feel it kick on and off in my truck with the Borla. I can even hear some flutter.

Back with the stock set up, I could not hear the difference but can still feel the difference.

On our old Honda odyssey, one could not tell or hear the difference at all.

  • Like 1
  • Haha 1
SS502 Senior Enthusiast

SS502

Posted
Posted
30 minutes ago, 3tspapat said:

My wife always says she can feel it going in and out....HAAHHAAH

No i'm not off topic...

I can actually feel it kick on and off in my truck with the Borla. I can even hear some flutter.

Back with the stock set up, I could not hear the difference but can still feel the difference.

On our old Honda odyssey, one could not tell or hear the difference at all.

Well I like the way you started the post lol I’m guessing like everything else on these trucks it’s hit or miss. Some have transmission shudders, some can’t get a drivers side grab handle to fit right. I have the 6.2 if that matters but I can definitely hear the switching but again, I’m rarely in Drive.

AtlasFBG2 Enthusiast

AtlasFBG2

Posted
Posted
On 1/30/2019 at 3:13 PM, F4Gary said:

I don't believe this for a second.  You can hear V4 mode, but you can't feel it go in and out.

On my 4.3 v6 when it went into v4 mode it could be felt. There was a vibration mainly around 35 mph and 50 mph.

 

I believe the cause of the vibration in v4 was the flapper valve. After changing to a MBRP exhaust the  vibration is gone and v4 mode can not be felt anymore. 

ftwhite Enthusiast

ftwhite

Posted
Posted

Can't feel or hear mine. Have to look.
2018 6.2L with MagnaFlow muffler, with factory resonator.
Flapper removed.
No CAI.
Blackbear AFM tune.

Sent from my SM-G960U using Tapatalk

3tspapat Enthusiast

3tspapat

Posted
Posted
3 hours ago, ftwhite said:

Can't feel or hear mine. Have to look.
2018 6.2L with MagnaFlow muffler, with factory resonator.
Flapper removed.
No CAI.
Blackbear AFM tune.

Sent from my SM-G960U using Tapatalk
 

I think I know the reason why you can't hear or fell anything.

  • Like 1

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • newdude
      Gasser Subforum Has Been Quiet - - So, Regenerative Braking and Using L10

      By newdude · Posted

      No such thing as regenerative braking on a pure ICE vehicle.     Regenerative braking is the re-capture of energy from electric motors and stores it in the battery pack.  So hybrids, PHEV and EVs have regenerative braking.     What you are seeing is the charging system changing modes is all.  Its likely entering charge mode for some sort of reason is all.  All of the charging modes will be listed below.   As for L10 vs D.  L10 turns off automatic grade braking.  L10 puts you in control of grade downshifts where in D it will automatically do it based on brake pedal position and other factors.  Otherwise L10 and D drive exactly the same aside from that one aspect.    Battery Sulfation Mode The BCM will enter this mode when the interpreted Generator output voltage is less than 13.2 V for 45 minutes. When this condition exists the BCM will enter Charge Mode for 2–3 minutes. The BCM will then determine which mode to enter depending on voltage requirements.   Charge Mode The BCM will enter Charge Mode when ever one of the following conditions are met:   Windshield wipers are ON for more than 3 s. Climate Control Voltage Boost Mode Request is true, as sensed by the HVAC control module via serial data. High speed cooling fan, rear defogger, and HVAC high speed blower operation can cause the BCM to enter the Charge Mode. The estimated battery temperature is less than 0°C (32°F). Battery State of Charge is less than 80%. Vehicle speed is greater than 145 km/h (90 mph) A current sensor malfunction exists. System voltage is determined to be below 12.56 V When any one of these conditions is met, the system will set targeted generator output voltage to a charging voltage between 13.9–15.5 V, depending on the battery state of charge and estimated battery temperature.   Fuel Economy Mode The BCM will enter Fuel Economy Mode when the estimated battery temperature is at least 0°C (32°F) but less than or equal to 80°C (176°F), the calculated battery current is less than 15 A and greater than −8 A, and the battery state-of-charge is greater than or equal to 80%. Its targeted generator output voltage is the open circuit voltage of the battery and can be between 12.5–13.1 V. When fuel economy mode is active, the generator is not charging, only maintaining open circuit battery voltage. The BCM will exit this mode and enter Charge Mode when any of the conditions described above are present.   Headlamp Mode The BCM will enter Headlamp Mode when ever the head lamps are ON (high or low beams). Voltage will be regulated between 13.9–14.5 V.   Start Up Mode When the engine is started the BCM sets a targeted generator output voltage of 14.5 V for 30 s.   Tow/Haul Mode (if applicable) Pressing the Tow/Haul Mode button located on the center stack, the vehicle system voltage is raised and the remote (non-vehicle) battery will be charged. Having the headlamps on will raise the system voltage and if the Tow/Haul button is applied it will not serve any purpose. The voltage is regulated between 13.9-14.5 V.      
    • jaszr2
      Active Grille Delete

      By jaszr2 · Posted

      Hello from Australia Just sharing that there is now a way to delete the active shutters entirely with just a plug in module. Opens up tons of room to light bars etc.
    • jake111
      Gasser Subforum Has Been Quiet - - So, Regenerative Braking and Using L10

      By jake111 · Posted

      I have an observation and a question... 1) I watch the voltage closely because I have had to dial in the cut-in/cut-out voltages of the battery separator to my camper.  The "smart" charging drives me nuts.  Anyway, I noticed that when coasting for a while, and especially if lightly using the brakes (though not necessary), the voltage goes up from mid/high-13 volts to mid/high-14 volts.  Then it drops back down after stopping or going again.  Consistently!   The only explanation I can come up with is REGENERATIVE BRAKING!  Well, maybe that's a little bit of an exaggeration, but it's certainly free extra battery charging.   2) Driving on mountain roads I will use L and vary the max gear.  Things straighten out and I end up in L10.  Sometimes I leave it there for a while.  Is there any difference between L10 and D?   
    • devonthegreat
      anyone interested in a 2002 Chevy Silverado 4x4 parts truck NYC

      By devonthegreat · Posted

      **SOLD** Please end or delete post. thank you
    • PBNB
      Tire pressure for 37s

      By PBNB · Posted

      Do you think this width might affect the chalk test with a higher pressure closer to 65psi? I think lowering the pressure makes sense to get the tread to lay flatter

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...