Active Fuel Management Reccomedations
Thread Starter
Racer
Joined: Feb 2001
Posts: 381
Likes: 8
From: NORTH WEST PA
Active Fuel Management Reccomedations
Question, is it worth it, or necessary to eliminate AFM on the C7s.
I just purchased a 2017 Z06 with 18,000 miles and I am looking for advice and suggestions regarding AFM.
Many Thanks!
Brian
I just purchased a 2017 Z06 with 18,000 miles and I am looking for advice and suggestions regarding AFM.
Many Thanks!
Brian
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Define "eliminate"? Just having the ECM shut off the AFM is not too bad when you program it out. As a side effect, in an auto you can certainly get the transmission shift a little different and change the tip in for the throttle with the Diablo unit. From what I read, it can do it and revert if you have warranty issues and nobody will know any different.
If you want to eliminate it altogether by removing the weak lifters, it might take a cam swap. In which case you can add a little performance to the swap when you get the delete kit. Obviously that is a bit more money. If you plan on modifications, not a problem. This is the way to go. The speed shops I casually ask tell me that is the way to go since those are the lifters that more often than not fail. That of course opens up another whole can of worms. You plan to keep it for a while to get the most out of the money spent? Are you racing it?
If you want to eliminate it altogether by removing the weak lifters, it might take a cam swap. In which case you can add a little performance to the swap when you get the delete kit. Obviously that is a bit more money. If you plan on modifications, not a problem. This is the way to go. The speed shops I casually ask tell me that is the way to go since those are the lifters that more often than not fail. That of course opens up another whole can of worms. You plan to keep it for a while to get the most out of the money spent? Are you racing it?
Pro
Joined: Mar 2006
Posts: 646
Likes: 72
From: EAST TEXAS
Since 2016, in two C7's, I have been using the plug in device from Range Technology. Just leave it in the OBD socket under the lower dash, and it prevents the engine from going into 4 cylinder mode. The latest version also automatically shuts off when you kill the engine so there is no battery drain when the car is parked. It is not a "tune", and when unplugged, the car goes back to normal factory function. I used to unplug it from time to time when doing some highway cruising just to see if the car would indeed go back to activating AFM. I would find a level stretch of road where I could just cruise at about 60-70 MPH, and either hold a steady throttle or set the cruise control for a mile or so, and yes it would go into 4 cylinder mode. Then I would plug the unit back in, and under the same conditions, it would stay in V8 mode. You can go thru the fuel information screens to find the one which displays whether the engine is in 4 or 8 cylinder mode.
If you do this, my suggestion is to buy it directly from Range, rather than ebay, or Amazon. That way, you are going to get the latest version, rather than one which may have been setting on a warehouse shelf for a few years.
If you do this, my suggestion is to buy it directly from Range, rather than ebay, or Amazon. That way, you are going to get the latest version, rather than one which may have been setting on a warehouse shelf for a few years.
Thread Starter
Racer
Joined: Feb 2001
Posts: 381
Likes: 8
From: NORTH WEST PA
Thanks for the replies. So, I'm not planning on racing it ... kind of. It may see a couple of quarter mile runs, and maybe a few street races but for the most part I was wondering if defeating AFM was helpful, necessary or detrimental in the long run.
Thank you
Brian
Thank you
Brian
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
It also sticks out of the port which is bad if you kick it. Having done this a couple of times, I figured it was a sign for me to get something else that was going to change the program and not use foolers on the ECM
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Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Thread Starter
Racer
Joined: Feb 2001
Posts: 381
Likes: 8
From: NORTH WEST PA
Brian
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
To be clear, the Range device or any other software just keeps the PCM from entering AFM mode. What fails are the AFM lifters. Those are still in the car in all their glory. One can debate if the Range device reduces the possibility of failure but the weak link is still in the engine.
Melting Slicks
Joined: Jan 2015
Posts: 2,105
Likes: 949
From: Fleming Island Florida
I had been using a Range AFM for the majority of the 80k+ miles on my '15. I would occasionally pull it to allow the AFM lifters to be exercised. Sadly, the last time I pulled it on my way to the dealer for an oil change, one of those lifters failed. It was a very costly event.
Now I have it disabled in the ECU firmware with the Diablo i3. As long as the signal to activate the AFM solenoids remains disabled, those lifters will never activate again. Sure, there's no guarantee something won't fail in the future, but short of doing a full AFM delete, I feel this is the best option.
Oh, and I would advocate AGAINST the use of a Range disabler. The risk of possible failure of the device or loss of connection by either poor connectivity or accidentally hitting it while getting in/out of the vehicle is too high.
Of course this could be debated 'til the cows come home. Just my opinion based on experience.
Now I have it disabled in the ECU firmware with the Diablo i3. As long as the signal to activate the AFM solenoids remains disabled, those lifters will never activate again. Sure, there's no guarantee something won't fail in the future, but short of doing a full AFM delete, I feel this is the best option.
Oh, and I would advocate AGAINST the use of a Range disabler. The risk of possible failure of the device or loss of connection by either poor connectivity or accidentally hitting it while getting in/out of the vehicle is too high.
Of course this could be debated 'til the cows come home. Just my opinion based on experience.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I had been using a Range AFM for the majority of the 80k+ miles on my '15. I would occasionally pull it to allow the AFM lifters to be exercised. Sadly, the last time I pulled it on my way to the dealer for an oil change, one of those lifters failed. It was a very costly event.
Now I have it disabled in the ECU firmware with the Diablo i3. As long as the signal to activate the AFM solenoids remains disabled, those lifters will never activate again. Sure, there's no guarantee something won't fail in the future, but short of doing a full AFM delete, I feel this is the best option.
Oh, and I would advocate AGAINST the use of a Range disabler. The risk of possible failure of the device or loss of connection by either poor connectivity or accidentally hitting it while getting in/out of the vehicle is too high.
Of course this could be debated 'til the cows come home. Just my opinion based on experience.
Now I have it disabled in the ECU firmware with the Diablo i3. As long as the signal to activate the AFM solenoids remains disabled, those lifters will never activate again. Sure, there's no guarantee something won't fail in the future, but short of doing a full AFM delete, I feel this is the best option.
Oh, and I would advocate AGAINST the use of a Range disabler. The risk of possible failure of the device or loss of connection by either poor connectivity or accidentally hitting it while getting in/out of the vehicle is too high.
Of course this could be debated 'til the cows come home. Just my opinion based on experience.
Some have said so, others have said it is like disabling it with the Range device except you can tweak a few more parameters. Either way, no guarantee it does anything. Only way to be sure is a cam swap.
I'm more worried about changing the OBD2 port. Any idea how big a PITA that can be?
Melting Slicks
Joined: Feb 2018
Posts: 2,184
Likes: 1,050
From: North Texas
If you break the OBD port connector your only choices would be:
Add a pigtail connector, not the cleanest route.
Find a replacement plastic shell and swap the wires to the new connector.
Lesson learned here is don't take chances in breaking the connector.
Add a pigtail connector, not the cleanest route.
Find a replacement plastic shell and swap the wires to the new connector.
Lesson learned here is don't take chances in breaking the connector.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Nobody ever kicks the unit until they do. Fortunately for me, 2 times was lucky and I wasn't going to see if the 3rd was too.
Melting Slicks
Joined: Feb 2018
Posts: 2,184
Likes: 1,050
From: North Texas
Just spitballing here:
Wouldn't it be nice, if possible, if some company engineered and manufactured lifters of the proper length that they could be just dropped in the AFM lifter holes without a cam change thus eliminating the dual action of the AFM lifters and all their issues? These lifters would act like the V8 mode was always engaged.
Kind a like a lifter and cam change but only the the lifters would be replaced.
These lifters would operate just like normal lifters but designed for only the AFM holes.
Not really sure if this idea is even feasible.
I'm on my first cup of coffee of the day...........
Wouldn't it be nice, if possible, if some company engineered and manufactured lifters of the proper length that they could be just dropped in the AFM lifter holes without a cam change thus eliminating the dual action of the AFM lifters and all their issues? These lifters would act like the V8 mode was always engaged.
Kind a like a lifter and cam change but only the the lifters would be replaced.
These lifters would operate just like normal lifters but designed for only the AFM holes.
Not really sure if this idea is even feasible.
I'm on my first cup of coffee of the day...........
