Are you saying that I am in the clear by a year and issues fixed? Brian, I just purchased and installed a remanufactured L76 AFM engine for my 2007 Suburban. He stated if I continued to exceed 4500 RPM it would blow the lifters out. Whats the next step? [], I have a 2012 Silverado Z71 bought new. in your opinion will this work, i really dont see any reason it wouldnt. I wii be using this truck to haul a camper for full time RV living and am thinking of a tuner to shut off AFM and maximize performance and economy. I have a 08 6.0L out of a Silverado with an aftermarket oil pan that has no provision for a pressure relief valve. A 17 with 5.3. Is there any potential down-side to doing this in other words, might this do more harm than good? Change your oil. Any help would be appreciated. The engine will operate on 8cylinders, or V8mode, during engine starting, engine idling, and medium to heavy throttle applications. Or not because it is the cast iron block and not he aluminum block? Question i just bought a 2005 Saab 9-7 with 5.3 v8, (same as GMC envoy) which came with AFM, the car runs fine, so if i just install the OBDII electronic device, is it just as likely that my lifters will still go bad? Also putting in a new transmission vs. rebuilding. Verified over hundreds of trips, makes no sense. With the AFM tuned off, it shouldnt be trying to switch over to four cylinder mode. Welcome to socialism folks . RANGE TECNOLOGY.COM. Here are a few of the issues that you'll want to keep on your radar if you drive a 2017 Chevy or GMC vehicle with a 5.3L engine in it. She started to have the lifter problem again after 60,000 miles more. You will be placed in derate if the ECM does not see the correct resistance from the ATF intake. I would appreciate any feedback. Replacing engine due to issues caused by AFM. It will show up as a misfire code in a cylinders 1,4,6, or 7. I just bought a 2018 Silverado. What type of ODBII gadget did you use? Brian, Thanks. Lost number four any help? 2012 5.3 Tahoe AFM, #4 lifter collapse,replaced all lifters,started engine ran ok, then rough, got #6 misfire code. I tried the trans fluid in the oil. Another General Motors 5.3L V8 Lawsuit Filed | GM Authority Very confusing stuff out there. After reading these forums Im a little concerned about my decision to stay with GM. Look for the following: TheAFMcover is called the Lifter Oil Manifold Assembly (LOMA). Seems my oil pressure sensor is bad, are showing the same oil pressure at all times, even when it dosnt run.Dont know it that fault was there before i replaced the lifters. bought at Brian Tooley Racing ! . Now i have my mechanic trying to follow a YouTube video I saw with a guy and a rod and a hammer. GM 6.2 Active Fuel Management Problems: What They Are and How - CarAraC HELP, I have 2005 envoy that runs makes lifter noise then dies in about 30 seconds then I started it one day and it ran with little noise for 5 min started next day and it starts and dies again got heads off was told I could put ls 3 lifters in is that true or is there something else I could do thanks Duane. I asked my local Chevy dealer, from whom I purchased the engine, to find out why the oil pan lacked the fitting. Correct me if Im wrong- If such an item was available couldnt you then just replace the lifters in the 4 AFM cylinders and then just run a disabler or have your ECM/PCM reprogrammed to have AFM disabled permanently. [] For more on that, read: How to Delete or Disable Active Fuel Management (AFM) on GM Engines. Disable the afm. So now at 168 thousand miles it still runs good but gets bad gass mileage. Thanks. Vehicle has 40k miles been maintained well and shows no signs of lifter concerns at present. Brian, we have a 2007 Yukon Denali in our shop with a 6.2L v-8 that has suffered a lifter failure with camshaft damage. Now I know why there wa such a push to get older ,less efficient vehicles off the roads. Ditto , never buy a throw away vehicle again is my recommendation and my fix . [], [] LS Tech: How to Delete VVT or DisableAFM []. A V8 firing all 8 cylinders sees 90 degrees between combustion events, while a 4 cylinder engine lengthens this to 180 degrees. Ever since that which was Feb/March 2020 i get a intermittent rattle does not do it all the time and I am not getting any codes i.e. If you already own this engine you will need to deactivate the AFM system or even better DO NOT buy any GM vehicle with this engine. .IMHO . Thank you. Now the problems back, I have 180k miles on it now. The only problem is the extra spray on the cylinder models if a deflector isnt used and this can show up as increased oil consumption. Hello! I went ahead and purchased a Disabler on Amazon, for preventing it happening in the future. The vehicles affected were 2007 to Feb. 2011 AFM equipped engines (Aluminum or Iron block-L94, LZ1, L99, LC9, LH6, L76, LFA, LMG, and LY5). With that said, the current global chip shortage has been affecting the industry on a wide scale, forcing production halt among several automakers. The L76 is an adapted version of the LS2, featuring new rectangle port cylinder heads and Active Fuel Management (AFM). NOTE: Some parts are not legal for use in California or other states with similar laws/regulations. How do you know if the lifter has failed? Its got a hundred forty-five thousand miles on it. Just recently, GM announced a temporary closure. I also have 08 Burb, but have different symptoms (high oil consumption, blue exhaust smoke at start, and now a really rough start after sitting overnight). I ran 0W-20 no more the 5000 miles between changes. This lowers the cost of building it [], [] aluminum block engine. It replaces the AFM components with standard parts. There has been a lifter noise since I bought the truck 1 year ago. PDF Service Bulletin Bulletin No.: 20-NA-038 Date: March, 2020 Next day, fired it up to take the the junk yard and it ran great. You may want to update your post. The engine will normally operate on 8 cylinders in V8 mode during starting, idling, and medium or . NOTE: You can find engine specs and detailed engine upgrade advice for every LS and LS-based Vortec truck engine in one place: The Definitive Guide to LS Engine Specs and LS Engine Upgrades. My 2011 Tahoe has a LMG motor in it with a build date of May 2011. Your email address will not be published. Call chevy.They should being paying most of that. The main misconception is that shutting down half the engine's cylinders reduces fuel consumption because the . The Hit and Miss Nature of Cylinder Deactivation Systems I have a 2011 GMC with over 162,000 miles on it and it runs great! Just one. Is there any reaction to the disabler when pulling a boat or trailer? Thanks for your help. All ready done valve job . When you don't need the full power of the engine, it provides better fuel economy." Any problems to watch out for?Did you replace the VLOM? Once I get it back, could I install the Disabler safely. There are so many moving components in an engine these days as opposed to the past. .That was a year ago and now I have a collapsed lifter and the most inexpensive repair $2200.00 for a partial lifter replacement. Any thoughts or suggestions would be appreciated. It is also known as Displacement on Demand (DoD) or cylinder deactivation. Excess oil will be pushed out of the pressure relief valve into the oil pan. It came back on last Wednesday starting with a flash. How about if they just let us have a manual transmission agains for fuel mileage? I remember those Other GM vehicles that the consumer tested for GM and paid GM for the honor. Was a disaster then but a profitable disaster. Is the Pressure relief valve replaceable? I got as high as 23mpg on the highway in my 89 K1500 with 350ci and a five speed manual. 1. Bought an 07 GMC Yukon 5.3 with the AFM, 87k. Dod is the biggest failure sence the 8-6-4 caddie in 1981. Sometimes it will do it all the time and other times can drive it for 10 miles and then it starts but doesnt do it constantly when driving. I am hoping this does the trick. []. There is a filter screen under the oil pressure sender that may be clogged and not getting enough oil to supply the solenoids. I know a few guys with Tundras. Most of the complaints show up in the 2009 to 2011 model years. There is a note in the TSB that states the bulletin doesnt apply to the LH6 used in the Rainier, Trailblazer, and Envoy due to a different design oil pan and AFM relief valve. I have always loved Ford and Chevys , I dont like this Vehicle not one bit, starring shaft has to be lubed or it whines, front A arms has done been replaced, tapping in motor, leaf springs has been lubed, retorqued, put completely new leaf springs back in on the rear , grease all down from rims to body of truck, you have to clean often,console shakes as if milk shakes in console which later they also put rubber bushings in front of coils of shocks ( front end) .You lock it down in 44 it s metal to metal , As of now Im at 32,000 done gone threw all the arbitrator laws depending on how it goes? Where can I buy a bolt to replace this relief valve ?? It essentially turns your V8 engine into a V4 which saves fuel. I recently bought a 2018 Silverado 5.3L with AFM. I would rather stay a V8 full time than deal with AFM issues in the future. AFMis good for gas mileage and can be 5-7 percent more fuel-efficient under certain conditions. Good point which begs the questuion, why does the Service Stabilitrak error seem to coincide with lifter failure? I recently took a long trip and it burned 1.5 quarts of oil. I have a 12 wit 4.8 Silverado 75000 miles How is that an improvement. Regarding the cylinder deactivation impact on fuel consumption . What makes you think it was a design flaw ? We were getting a code that the cam position sensor was not functioning properly. My 5.3 is. Pushing forward. Its not GMs choice to use AFM. I had #4 lifter stick and now i am looking at replacing the engine with a non-dod version. Replaced all lifters. I know I felt the same way. I have a 2011 Chevy Tahoe with the 5.3 Gen 4 LS (VIN Code 0) and I bought a CAM motion DOD/AFM delete kit, 3 bolt drop in CAM Motion stage 2 camshaft, VVT delete kit and finally a Diablo Predator 2 Premium for GM programmer. Traded it with 180K miles and did not experience any problems. . https://www.cargurus.com/Cars/Discussion-t30884_ds822284. It was in the late 70s or early 80s and it was a POS, Your memory serves you pretty well I too have the same nightmares lol. Why have you not gotten a reply from Mr Nutter, Buying a Silverado 6.2L. Given that, would you recommend buying one of the OBD-II devices to disable AFM? I have seen more internal engine failures in the last 5 years or so than I have in the first 15 years in the business. How to Delete or Disable Active Fuel Management (AFM) on GM Engines Power will be sent to the rear axle via a beefed-up 4L60E [], Have a problem with 09 Chevy It does seem that when they start goingthey go quickly. Since the tranny oil worked, you should now change the oil, right? Unfortunately because of emission standards nowadays, manufacturers cant go back to those style of engines. This valve is located on the oil pan rail and prevents excessive oil pressure from negatively impacting the AFM components. The trucks are only supposed to use two four. That inherently less smooth operation requires additional NVH dampening. Dave, I also have a 2008 LTZ avalanche with 106,000 I have the exact same symptoms at this point I just want to sell it will the disabler help remove the check engine light wont pass inspection with light on thanks for your help Chris. thank You so much! Given maximum engine power is not required during the majority of everyday driving, AFM works to deactivate engine cylinders when they are not needed, such as when cruising on the highway, thus. He used seafoam and changed to synthetic oil. You may eventually see a check engine light from a misfire code and the ECM dialing everything back to protect your engine. We need availability of a replacement engine without the AFM. The dealer in Rockhill, SC when asked only said they had not had a problem. My 2002 I had over 298K on it with no engine related issues. 2015 SILVERADO 1500 44 crew cab with 5.3L engine: So two weeks ago with approx 70K miles, I had an odd noise when accelerating and then engine light flashing and riding rough. whith a disabler. I had a 2007 Yukon XL 5.3 with the AFM. Oil 0w or 5w -20 Brian, I have been reading your article about the AFM. Problems regarding Chevy 5.3L engines ticking noise and misfire. They dont so any better than domestics on mpgs. Install the AFM disabler now or wait until my warranty just about to expire to get this AFM issue resolved? It has AMF. My Wifes 17 Buick with afm was my attempt to get back to gm. We had one for a company car in 82 and it never did run right from new but at least it didnt destroy itself. I only have ~ 5k miles on it, and it hasnt been driven hard, so Im assuming the lifters are fine. You also need the disabler installed in your obd connector. Another option is to plug it entirely if the AFM is already removed. Ive only put a straight pipe exhaust, intake, and a boost controller on it. If you just crack it without it starting it moves all the time . Perhaps a flaw by design would be a more appropriate description . Toyotas 5.7 is one of the biggest gas guzzlers among half-ton trucks. Is this the shield you referred to in a past post? This should be added to your earlier model if you experience oil consumption. It looks as if Ill need to start saving for a complete AFM delete kit with a new cam. If possible, will simply not using VVT provide a powerful,good running engine? Thats a tough call, if the warranty will cover itId let it run out. [] For more information on AFM, including a comprehensive guide on how to completely remove it from your engine, check out this article. I have successfully used a gadget that plugs into the ODBII. I am worrking on a 2007 chev Silverado 6.0 engine, [] the L76 that was equipped with AFM and had a ribbed valley cover, the L98 cover was []. The collapsed lifters will not engage the pushrods and both valves remain closed. After taking a $3.6h bath on the lifter/valve work and doing a little research, how can GM allow a problem like this AFM continue from 07 to present? I may just do that Vic. No clue what to do. Some guys have been able to use a tool through the top with the cover off to get it to release. Both #6 lifters only move when turning engine by hand, if you use the starter they stop moving. If you installed a factory truck cam, there shouldnt be any particular reason for it to be down on power. Why doesnt anyone make an aftermarket set of replacement AFM lifters that are the right length but DO NOT COLLPASE! so the trans fluid worked for you then? There is a chance the cam lobe was stressed and started to deteriorate. You can monitor the oil level on your dipstick for 3,000 miles to determine if the deflector or plug would be needed, but chances are you wont based on the TSB. It only has about 9k miles on it. Why cant you stop the send signals from the computer so that the solenoids dont open and the AFM system is never engaged? Did Obama make them do this? An electromechanical system deactivates and reactivates all 16 of the engine's hydraulic valve lifters, controlling valve actuation. They learned that the oil level sensor was necessary and that we were supposed to have been advised that we needed to reuse the original oil pan. I am trying to find out of this is true. They layed over night in engine oil before instalation. Took it to the dealer and was told I had a collapsed lifter. I had purchased an extended warranty when I bought the truck new. Learn how your comment data is processed. My question is: do I install the electronic disabler on the new engine to avoid future issues? do you fill to capacity anyways???? they are known to become plugged. I wear hearing aids, but I thought I heard more engine noises, but after checking the gas cap, the light went out for a week. I told her to never pull the gadget out. Well, they move a couple of times after startup thats all.Asume its the same on syl 7 on the other side.Disconected the Connector to the solenoids, no difference. My concern is if I leave the non-AFM lifter cover in place & have nothing to plug the 5 pin AFM solenoid connector into, will I get a MIL? Cylinder Deactivation: What Is It and How Does It Help Save Fuel? of cranking pressure because the duration is longer on those cylinders to being with to offset the AFM lifter design. I want to put a AFM disabler in it what all do I need to have done. Thanks. This really sucks. The 2nd went with a conventional valvetrain. My 2013 GMC Yukon XL 6.2L is currently having a failed lifer replaced. The cherry on top is its not saddled with Variable Valve Timing (VVT) or Active Fuel Management (AFM) found on some Gen. 4 engines. Would it be fine to go ahead with the AFM Disabler? But the problem at that time was the computer technology. The engine has flex-fuel capability. What can I expect with the AFM in place, or, with AFM disabled (not deleted)? Im considering just replacing the 5.3 ( should be LMG, 2007 YUKON ) with the L96 crate engine. This update also saw the usage of cylinder deactivation technology or Active Fuel Management. Should I buy a Diablo AFM disabler to prevent the new block from dropping to 4 cylinder? Have an 06 Yukon with 5.3, original engine had bad knock, was told it was lifters so had them replaced. Dont drive it if you have a dead cylinder due to afm failure. For a primer [], [] cathedral port cylinder heads and used Active Fuel Management (AFM). If you think GM pioneered cylinder deactivation, guess again As you said, the ECM was never seeing the AFM so I think youre good to go. the extra oil isnt needed. There are 5.3 cylinder deactivation problems that can occur. It has 8,000 miles on it. There is no light on my dash or anything that indicates the system is active or exists, so its very confusing, Im still not sure if my vehicle has it or not. The tune is the best bang for the buck outside a cam swap anyway and what Id recommend. He claims that GM used the same engine whether it was or was not equipped with AFM in this year and model? Theyre also notorious for bad cam tower oil leaks. I could just transfer over the AFM lifter cover, but it is really nasty on the bottom side & I do not want to risk damaging this replacement engine if it is loaded with debris from the lifter & camshaft failure. GM should recall every vehicle with this terrible design flaw! If you installed a performance cam intended for a car, it may be bleeding off some low end compression. Friend will send to me from Arizona. There are no changes in the valves or the springs. Batten, followed by several years developing performance pistons at Wiseco Piston Co. Today, Brian develops performance parts for Summit Racing Equipment and is a regular OnAllCylinders contributor. The cost of just rings $4,000.00, [] Disable your Chevy AFM: https://www.onallcylinders.com/2017/11/30/how-to-delete-or-disable-active-fuel-management-afm-on-gm-… [], [] like front timing cover, knock sensor location, cylinder head style (cathedral ports), AFM (Active Fuel Management), and other components are key clues to which engine family youre looking []. Im crossing my fingers it does the trick! Keith, sometimes they will only replace one lifter rather than the whole setIf thats the case, another lifter can fail again pretty quickly. The engine was not Flex Fuel (E85) capable and did not use Variable Valve Timing (VVT) [], [] TheL76like its LS2 siblingis a 6.0L, Gen. 4, aluminum small block engine that was used both in GM cars and trucks. I didnt even think about AFM until I got to drivee it on the highway and encountered the 4 cyl syndrome. General Motors Active Fuel Management Cylinder Deactivation Technology Active Fuel Management (AFM), otherwise known as Cylinder Deactivation is a General Motors engine technology that. A 17 with 5.3. 91 GMC Sierra K1500 F44 6.2 NA Plow truck with 7.5ft Leo Plow 94 K3500 CC DRW 6.5TD DE exhaust . Most will want to get rid of the AFM immediately. A problem with cylinder deactivation can be solved by tuning the intake and exhaust valves. Have not had a problem yet. GM switched over to the 4100 v-8 in 1982. what deleter (if thats a real word) have you heard good things about. The pressure relief in the pan opens at around 45psi to prevent over pressurization of the vlom solenoids. Engines withAFMalso use a special camshaft, a high-volume oil pump, and a pressure relief valve in the oil pan. He unstuck it and I took it for a drive and same thing happened. The materials used in the engine were [], I have a 2018 GMC with the Eassist and AFM My 2013 LC9 just had #6 lifter fail, got a misfire code but the ticking gave it away. Hi Brian please help, yesterday after ice fishing was climbing a hill back home and check engine light flashed. [], [] Its a Gen. 4 5.3L iron-block engine, so youre getting the better intake manifold, connecting rods, and ECM. I pulled the head off, replaced the lifter and put the gadget in the ODBII for about $400 total. (Non-AFM engines have a smooth cover.). GM's Active Fuel Management (AFM) works under certain light load driving conditions to maximize fuel economy by deactivating 4 of the engines 8 cylinders. I have 1999 5.3 Silverado that gets 19-20 miles to the gallon all the time this shit pile with dod only gets 14 miles to the gallon. Drives way better for my mostly paved road driving. Cylinder Deactivation & Variable Engine Displacement - LiveAbout Sylinder one lost compression on my 09 5,3. Now im thinking of buying a disabler asap, am i in the clear to do so without the oil splashing problem? Now you tell me AFM works and I will tell you; that you are full of shit! I did noticed the oil consumption but it was rare that I would have to add oil. CAM motion says no just have to disable the AFM and VVT with a stock tune as the camshaft is not an aggressive camshaft but a drop in. I noticed this discussion mainly addresses Chevy Silverados and other trucks? The market for nonhybrid gasoline-powered vehicles is expected to fall by 20 percent during that time, but with tech like smarter cylinder deactivationin these upcoming GM V-8 trucks, for . Hi Grant is that disabler still working for you ? Wow, thanks for the wisdom,, i checked my VIN Code (position #8, M=LH6) and my 2005 Saab 9-7x does have the LH6 motor with iron block, Are you sure its only 2007 & newer motors? 2017 5.3 Liter Chevy Engine Problems: Be Aware of These 4 Issues! More information can be found in the GM TSB bulletin number 10-06-01-008g. When you eliminate the AFM system, the extra oil is no longer needed. I have no other engine problems and Id like to fix the issue. Clean oil is crucial. Thank you again for the response. Problems After AFM Delete And How to Solve Them? - Tools Bible [] engines is that when VVT (variable valve timing) appeared and was later followed by AFM (which is Active Fuel Management, when the engine deletes four cylinders under light load) both of these packages drastically affect []. We are looking into the AFM Disabler option, but my question is- how do we know if a lifter is already bad or not? According to CarComplaints.com, several drivers have had excessive oil consumption issues for a while from 2007 to 2011. [], [] way. The motor I pulled was a 2007 LY5 with about 77k on it. No problems with any to this point. Took it in this morning and mechanic said cylinder 6 misfire, he said the lifter hasnt failed. Fortunately I received a reducing in house shop hourly rate. If I were to put a 2006 5.3L in a 2007 Avalanche and buy the unit to plug into my OBD2 port would it work? The early part of his automotive career included working for engine builders Scott Shafiroff and C.J. They replaced all the lifters, said no other damage, problem lifters were on cylinders 6 and 7. But then she passed away from cancer. Does cylinder deactivation affect engine life? - Quora If you want to delete it entirely, its a M14 x 1.5 pipe plug or you could use the Improved Racing plug p/n IRP-814-M14-Kit. No movement on the rocker arms. You cannot compare them to old 350s. Chevrolet 5.3 Engine Issues and Recommendations It was the first Gen. IV LS truck engine and offered Active Fuel Management (AFM). Regards, I have a Yukon 116k it now needs its 3rd set of lifters and cam. The oil pump is high volume, but there are a lot of people that dont change it and rely on the pressure valve to keep the volume manageable. Dont follow just anybody I know where it originates but in todays world I found found it to be amusingly accurate. I have 4 GMCs in my driveway right now only one with AFM its always popping DTCs, 06 Yukon (not AFM)never had a light in 12 years! 50,000 miles. What would you do if you were in my situation? I am leaning heavily on installing the AFM disabler. But if you dont like it. The problem I am facing is that I want to drive this vehicle for at lease another 77K and do not want to drive my vehicle with this AFM issue. Engine starts but is throwing a misfire on cyls 4,7. Jusy 3 weeks ago I quit driving it because of the lifter, but it worked fine when i started it back up. The biggest difference between the Vortec engines that used to be found in Chevy and GMC vehicles and the EcoTec engines found in them now are the fueling methods. Hi my name is noel I am a mobile mechanic and I have a client that was having trouble with the lifters on a 2011 gmc yukon Denali 6.2 I placed the lifters after finishing I still had a problem with cylinder 8,6,3 rocker arms were not moving so I replaced the cam OEM part but still having miss fire on cylinder 6 what should I do to get rid of this problem, [] computer cannot switch over to four-cylinder mode. 5.3-liter Chevy Engine Problems: What Should You Look Out For? I wouldnt trade my 2000 Silverado, 5.3 liter that has constantly gotten 20 mpg since I bought it 15 years ago, for a dozen of these new $50,000 POS. Vortec 5300s featuring LH6 and LC9 engines are prone to failing spark plugs due to carbon build-up. Install the disabler when you get your Yukon back and it will remain in good working order. My 2012 Silverado 5.3L just did the same thing as your Tahoe Brian. Definitely dont want to do anything to fix one problem and create another. Accept i only have 60K on my truck and it hasnt recovered. Its a simple and effective way to turn off the AFM system and provides the added bonus of improving exhaust sound. misfire or anything. http://www.autoserviceprofessional.com/article/91652/ticking-gm-v8-lifters-and-dtc. Question is, since my 2004 ECM and wiring harness were made before the AMF came about will this motor work properly as a V8 or will I need to replace the lifters, cam, oil sensor, etc as the delete method mentions? I have an 07 Silverado 1500 ltz. Vehicle has been serviced more regular than the manual calls for and the AFM has caused problem after problem with fouled plugs. I had one fail and it chattered the cam to the point that I had to Install a new cam. Did gm make a non-dod version of the 5.3 with iron block that would work in my application? There are so many more oil passages on engines these days. It also has an electrical connector on the back. All Cylinders. Brian, I have the same question as Scott. Im praying that my RangeTech buys me a few years. Im servicing a 2011 Chevrolet 5.3 with AFM. the body is in great shape. Yes a poor design but a flaw ? A 14 gmc 5.3 Sierra 85000 miles Truck has an active P0300 code and runs very rough. Below youll see references to the L99 as a result. Constant engine and transmission problems. Dont want to make a move on a new truck or jump to a 2500 yet. 190k on the motor always ran AMSOIL full synth since new. Cant believe they havent fixed this in a decade. (Bought car 1 day before lifter died!) I plan on getting a tuner to disable the AFM. Chevrolet Silverado 2014-Present: Common Problems 2 15 with 5.3 Sierras both with 100k and I own a reputable repair shop. Its job is to direct the flow of pressurized engine oil to the active fuel management intake and exhaust valve . Cost about $250, but it is not fool proof. New plugs and wires. If a shop pulled a DTC code P0300 and found AFM to be the issue, it may not be too late to try the disabler. But after reading this thread, Im a little concerned about the long-term reliability. It was well researched and tested back in the late seventies and eighties . I have a 2014 Silverado with a 5-3. I read something the other day which I found to be funny.