New member here trying to decide if I should delete the AFM or not. Engine is currently apart.

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JJ1971

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Hello I am a new member here and I have not owned a GM Vehcile in about 20 years. I just acquired a 2018 Denali with multiple issues with the AFM system. I pulled out 2 bent push rods, 1 lifter that came out in 3 pieces, The cam shaft has enough wear that it's getting replaced. I crunched the numbers using all GM OEM parts to repair the system which includes a new VLOM vs buying a delete kit. At this time I was considering the AMS Racing kit which includes a Diablo hand held programmer. The price to either repair vs delete are about 150.00 only in total.
I am curious if GM has updated the AFM/DOD parts since 2018 and if they are any more reliable. I am big on keeping things OEM but with this AFM system having so many issues I am considering deleting. I understand it would lose about 8% MPG on the highway or under light load. Not sure if the fuel savings over time would be worth it if this AFM system fails again. How has the reliability been after replacing the damaged AFM parts over time. How many miles have people been getting or is this simply still a gamble? If I do delete what is the opinion on the Diablo tuner vs paying someone or purchasing HP tuners setup? I need to make this decision very soon as this Yukon is tying up my bay and I need to order parts. Thank you.
 

Joseph Garcia

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Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

I believe that the overwhelming opinion of members on this Forum is to delete the AFM, as it is a known point of failure on these engines. Specific delete kits are offered by many vendors, and popular vendors for these kits, along with plenty of technical support as needed are Texas Speed and Summit Racing.
 
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Do an AFM delete and don't look back. My experience with a 2013 Silverado (full AFM delete) and a 2020 Tahoe (AFM turned off in ECU) is that you won't notice any change in mileage.

On both trucks I used a Superchips tuner with good results. They come with a few canned programs for slightly improved performance, shifts, etc.

The basic tuners work fine if you stick with a stock cam. If you go with something pepped up, you'll need a custom tune.
 
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JJ1971

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Thank you! I ordered a full delete kit today from AMS Racing along with about 100 other parts from the dealer. I own a Jeep shop and I have been dealing with Chrysler parts all these years. I cannot believe how inexpensive GM parts are in comparison I am literally blown away! Someone asked for pictures it really looks like any other one but here are some. It broke down in California and I paid to tow it back to Maryland since the price was right. This is for my wife to replace her Minivan so she can drive something and have pride and actually move out of its own way.
 

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89Suburban

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Thank you! I ordered a full delete kit today from AMS Racing along with about 100 other parts from the dealer. I own a Jeep shop and I have been dealing with Chrysler parts all these years. I cannot believe how inexpensive GM parts are in comparison I am literally blown away! Someone asked for pictures it really looks like any other one but here are some. It broke down in California and I paid to tow it back to Maryland since the price was right. This is for my wife to replace her Minivan so she can drive something and have pride and actually move out of its own way.
While you are in there and have the room to get to them, replace the heater hose firewall Tee's with metal ones.
 

West 1

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I have repaired many AFM engines, only done the delete 2 times. The best way to do the delete is to go into the GM Computer, I believe the Tech 2 allows you to switch the AFM system off. It asks if the vehicle has AFM, you answer yes or no. When you answer No it is gone from the software. A smog shop check no longer see’s that the vehicle had AFM from the factory. It has been a few years since I did the last delete but that was a better option than using tuners to do the same.
 

89Suburban

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I have repaired many AFM engines, only done the delete 2 times. The best way to do the delete is to go into the GM Computer, I believe the Tech 2 allows you to switch the AFM system off. It asks if the vehicle has AFM, you answer yes or no. When you answer No it is gone from the software. A smog shop check no longer see’s that the vehicle had AFM from the factory. It has been a few years since I did the last delete but that was a better option than using tuners to do the same.
I have not heard of this procedure?
 

Marky Dissod

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I have repaired many AFM engines, only done the disable 2 times.
The best way to do the disable is to go into the GM Computer, I believe the Tech 2 allows you to switch the AFM system off.
It asks if the vehicle has AFM, you answer 'yes' or 'no'. When you answer 'No', it is gone from the software.
A smog shop check no longer sees that the vehicle had AFM from the factory.

It has been a few years since I did the last disable but that was a better option than using tuners to do the same.
Fixed it for you. The above refers to disabling / turning off the feature.
Think very early L92 - they came with the hardware, but the feature was DISABLED,
before GM DELETED all Enginre Half@$$ parts from the L92 & L9H.
'Delete' refers to PHYSICALLY REMOVING the Engine Half@$$ hardware.

JJ1971, delete whatever cylinder deactivation hardware you might have.
Don't forget to disable the feature in the tune as well.
If you experience an 8% MpG penalty, you used to drive like a hypermiler.
 

2017sltXL

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Thank you! I ordered a full delete kit today from AMS Racing along with about 100 other parts from the dealer. I own a Jeep shop and I have been dealing with Chrysler parts all these years. I cannot believe how inexpensive GM parts are in comparison I am literally blown away! Someone asked for pictures it really looks like any other one but here are some. It broke down in California and I paid to tow it back to Maryland since the price was right. This is for my wife to replace her Minivan so she can drive something and have pride and actually move out of its own way.
Do you plan to freshen up the heads?
Money well spent if you are in it that far.
 

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