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Cylinder Deactivation Issues?

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Gotsumpnferya Enthusiast

Gotsumpnferya

Posted
Posted

I'm a bit conflicted about AFM . It is very dependent upon your driving style and load whether it is active . I drive the truck normally

95% of the time , but from time to time like to open the throttle and feel that V8 pull . On the highway trips , I don't mind

the V4 activation as long as it isn't causing undue wear on the components and that it is actually saving gas .

I'm trying to be confident with the evolution of these engines over the last several years that they've eliminated most issues ,

but the ticking I get at cold idle (post in another thread) has me cautious .

I live in the mountains of W NC and have driven many of the roads here which is fun , but I don't care for the AFM

coming on during those times .

 

I thought about one of the AFM disabler , but if I'm going to apply the money towards one , why not apply that

to a tuner so I can approach the transmission constantly trying to find the right gear or lugging as well ?

 

What I'd like is to have economy when I want it . I just wish GM had given us the option .

So hopefully a tuner will help with that once warranty is out . It's hard not pulling the trigger now .

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pickmeup
pickmeup

One simple button with a choice . Economy or Sport mode . I believe it would have saved many many complaints .

j-ten-ner
j-ten-ner

You're not the only one. Because it's easier to turn of AFM than adding two cylinders.   so long j-ten-ner

Grumpy Bear
Grumpy Bear

Well I can see the difference right away. I don't have much flat ground and around here, Chicago area big wind is life. That said. Being on and staying on is quite something else. Yea, it turns on but

Loco-diablo Senior Enthusiast

Loco-diablo

Posted
Posted

In the 6 weeks/3000 miles I owned my 5.3 AFM, I must say I'm very happy with it's seamless operation. I see it go from 4>8 and 8>4 but it's barely noticeable imo. I have no desire to inactivate it or modify it. So far, so good.

 

 

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Orlando8 Enthusiast

Orlando8

Posted
Posted

In the 6 weeks/3000 miles I owned my 5.3 AFM, I must say I'm very happy with it's seamless operation. I see it go from 4>8 and 8>4 but it's barely noticeable imo. I have no desire to inactivate it or modify it. So far, so good.

 

 

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:thumbs:

  • Like 1
B_SKY33 Enthusiast

B_SKY33

Posted
Posted

Very first thing I did was by a tuner and turn off the AFM, I don't like it or need it. Not to mention the exhaust sounds terrible when it goes into V4 mode. I've heard a lot of guys run the Range AFM disable tool but have had issues with it because it stays plugged into the OBD2 unlike a tuner.

dorkweed Enthusiast

dorkweed

Posted
Posted

Very first thing I did was by a tuner and turn off the AFM, I don't like it or need it. Not to mention the exhaust sounds terrible when it goes into V4 mode. I've heard a lot of guys run the Range AFM disable tool but have had issues with it because it stays plugged into the OBD2 unlike a tuner.

 

 

Not if you use one of these handy things..........................http://www.ebay.com/itm/OBD-2-Cord-16-Pin-Cable-Power-Switch-M-F-Right-Angle-ODB-II-Diagnostic-Splitter-/291761971818

  • Like 1
Nanotech Environmental Enthusiast

Nanotech Environmental

Posted
Posted

I'm a bit conflicted about AFM . It is very dependent upon your driving style and load whether it is active . I drive the truck normally

95% of the time , but from time to time like to open the throttle and feel that V8 pull . On the highway trips , I don't mind

the V4 activation as long as it isn't causing undue wear on the components and that it is actually saving gas .

I'm trying to be confident with the evolution of these engines over the last several years that they've eliminated most issues ,

but the ticking I get at cold idle (post in another thread) has me cautious .

I live in the mountains of W NC and have driven many of the roads here which is fun , but I don't care for the AFM

coming on during those times .

 

I thought about one of the AFM disabler , but if I'm going to apply the money towards one , why not apply that

to a tuner so I can approach the transmission constantly trying to find the right gear or lugging as well ?

 

What I'd like is to have economy when I want it . I just wish GM had given us the option .

So hopefully a tuner will help with that once warranty is out . It's hard not pulling the trigger now .

(underlined)

GM did give you that option. That's why AFM exists. When you want fuel econ, drive with a light foot and let the AFM work in your favor. When you want to giver, just do so. V4 only comes on during lighter loads, so it's not like it gets in the way when trying to pass, or accelerate up a hill or whatever hard throttle application you can think of. It doesn't get in your way, at all, ever.

Gotsumpnferya Enthusiast

Gotsumpnferya

Posted
Posted

(underlined)

GM did give you that option. That's why AFM exists. When you want fuel econ, drive with a light foot and let the AFM work in your favor. When you want to giver, just do so. V4 only comes on during lighter loads, so it's not like it gets in the way when trying to pass, or accelerate up a hill or whatever hard throttle application you can think of. It doesn't get in your way, at all, ever.

You're right , it doesn't get it the way , however it does come on at times when I don't want it to . Constant cycling on and off during mountain driving gets annoying , no matter how seamless others may find it . I don't feel as if I have to ride around in M5 all the time to get rid of it . The grade braking feature shouldn't reset during an ignition cycle either . It should be my choice .

 

Say you're in a boat or aircraft , and you're coming through a bad inlet or takeoff or landing , and some feature kicks in changing applicable power in some way at a time you don't want it .

 

Wouldn't you want the option of disabling that feature ? I know I would .

lloydsmale Enthusiast

lloydsmale

Posted
Posted

Question. If I buy a diablo tuner will it allow me to shut the cyl deactivation off at only high speeds? I heard the hypertech does but they don't make one for the 17s. Id like to set it for 60mph and eliminate it kicking in and out around town. Also if I have the 87 oct canned tune installed and cylinder deactivation shut off and go in for service and put the stock tune back in so the dealer doesn't see it do I first have to turn the cutout back on before I install the stock tune or does it automatically come back on with the stock tune?

Nanotech Environmental Enthusiast

Nanotech Environmental

Posted
Posted (edited)

You're right , it doesn't get it the way , however it does come on at times when I don't want it to . Constant cycling on and off during mountain driving gets annoying , no matter how seamless others may find it . I don't feel as if I have to ride around in M5 all the time to get rid of it . The grade braking feature shouldn't reset during an ignition cycle either . It should be my choice .

 

Say you're in a boat or aircraft , and you're coming through a bad inlet or takeoff or landing , and some feature kicks in changing applicable power in some way at a time you don't want it .

 

Wouldn't you want the option of disabling that feature ? I know I would .

Why are you choosing to get annoyed with it?

 

When your truck floats or flies, then you can worry about it. Until then.......... ;)

Edited by 3beejay3
  • Like 1
Loco-diablo Senior Enthusiast

Loco-diablo

Posted
Posted

As mentioned, I find the AFM operation pretty seamless, but that's not to say the owner shouldn't have the choice to disable it.

I absolutely believe that GM should allow you to turn it off if so desired. Government/EPA red tape I'm sure.

B_SKY33 Enthusiast

B_SKY33

Posted
Posted

Question. If I buy a diablo tuner will it allow me to shut the cyl deactivation off at only high speeds? I heard the hypertech does but they don't make one for the 17s. Id like to set it for 60mph and eliminate it kicking in and out around town. Also if I have the 87 oct canned tune installed and cylinder deactivation shut off and go in for service and put the stock tune back in so the dealer doesn't see it do I first have to turn the cutout back on before I install the stock tune or does it automatically come back on with the stock tune?

Hypertech now has a tune available for the 2017's. The AFM settings on it allow you to set it up for certain speeds or disable it completely.Its very easy to put it back to stock (less than 5 min). I actually am selling my Hypertech if you're interested, it's part#2000 that I tested on a 2017 Silverado. Save you some money if thats what you're looking for

Thomcat Senior Enthusiast

Thomcat

Posted
Posted (edited)

I agree mostly, I got 16MPG with my 73 Impala 454 with a 373 rear......

Unfortunately 1973 was not 1974. The 4-6 mpg on my '74 Impala 454 was a different animal not only because I didn't buy the largest engine to drive like granny to save gas, but Uncle Sam had a lot to say about it. The1974 model year - Oil Embargo - gas lines - odd/even plates - gasoline theft from parked vehicles! That was the banner year when the Gov't severely increased air pollution requirements and thus introduction of new experimental vacuum operated gizmos to please Uncle Sam while choking the engine and wasting gas at the same time. Even Chrysler had enough brains to at least introduce electronic ignition - but not '74 GM. Worst year to buy a new Chevy mpg wise, increased weight, coupled with jacka$$ safety standards like the infamous short lived driver seat belt ignition interlock and (tail lights out of the bumper in favor of heavier super duper 10 mph impact bumpers on gas pistons. The best was the low mounted gas filler with vented cap located behind the license plate....more than 3/4 fill in the gas tank and with every fast start and stop you wash the rear bumper with 1/4 gal. gas. But, even at $1/gal. it's poor gas mileage was worth it - the best riding car I ever owned - my less than 1/2 the weight '17 Impala is a cracker box by comparison..

Edited by Thomcat
  • Like 1
KARNUT Senior Enthusiast

KARNUT

Posted
Posted

Unfortunately 1973 was not 1974. The 4-6 mpg on my '74 Impala 454 was a different animal not only because I didn't buy the largest engine to drive like granny to save gas, but Uncle Sam had a lot to say about it. The1974 model year - Oil Embargo - gas lines - odd/even plates - gasoline theft from parked vehicles! That was the banner year when the Gov't severely increased air pollution requirements and thus introduction of new experimental vacuum operated gizmos to please Uncle Sam while choking the engine and wasting gas at the same time. Even Chrysler had enough brains to at least introduce electronic ignition - but not '74 GM. Worst year to buy a new Chevy mpg wise, increased weight, coupled with jacka$$ safety standards like the infamous short lived driver seat belt ignition interlock and (tail lights out of the bumper in favor of heavier super duper 10 mph impact bumpers on gas pistons. The best was the low mounted gas filler with vented cap located behind the license plate....more than 3/4 fill in the gas tank and with every fast start and stop you wash the rear bumper with 1/4 gal. gas. But, even at $1/gal. it's poor gas mileage was worth it - the best riding car I ever owned - my less than 1/2 the weight '17 Impala is a cracker box by comparison..

My mistake mine was a 74, factory 350-350-273 rear. I had a salvage yard at the time. I put a built 454 in it and a 373 posi. Later a transmission shop owner friend was experimenting with the 700R4 which my car was the giny pig. My wife's DD in the 80s. I even drag raced it a few times 14.7 was the best on street tires. I later put the 454 in a 76 nova.

 

 

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Newell33 Enthusiast

Newell33

Posted
Posted

(underlined)

GM did give you that option. That's why AFM exists. When you want fuel econ, drive with a light foot and let the AFM work in your favor. When you want to giver, just do so. V4 only comes on during lighter loads, so it's not like it gets in the way when trying to pass, or accelerate up a hill or whatever hard throttle application you can think of. It doesn't get in your way, at all, ever.

 

You understand that the AFM transition is not seamless in every truck, right? You may be one of the lucky ones, but others have serious lugging, hesitation, and transmission clunking concerns during AFM operation. I'm a reasonable guy, and if I wasn't able to turn AFM off on my '14, I would have taken a bath and traded it right away. Yes, it was that bad.

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