Exactly this.. My first 2014 was an Auto and I installed the range device and left it there when I sold the car at 68k miles.. My last car was a manual and it never went into ECO mode.. Put 60k miles and sold it at 87k miles with no issues with AFM.. Just got a 2016 Z06 and it will also Never go into ECO mode..

 

I'm going to call b.s. on the not using it it can fail the manual doesn't use it unless in eco mode. SO if this was a concern they would tell you to exercise the system if it was needed.

 

True. Nice sounding theory, does not work in real life.

 

It's all theory right. I don't ever plan on using AFM ever so for me it's a mute point. In Fl no inspection so I never have to remove it.

 

I used the Diablo. Nothing to kick. I had to be careful each time I got out. In the few months I had it, I must have kicked it out 3 times. Supposedly I get better throttle response and better shifting with the Diablo but for sure, I eliminated the AFM and nothing to kick or be careful of kicking. Scared to damage the OBD2 port. Passes inspection without having to de-program it.

If I believe that exercising the AFM theory, I'd be taking the tune in and out every so often. Royal PITA.

 

I will eventually get a tuner my warranty is good till 2027 so can't right now

 

A forum member DCASOLE said it doesn't change the file they use to track change of the ECM program

 

Did you look at this thread? Unsure if it contains the info you are looking for but...
A8 Transmission failure tracking - CorvetteForum - Chevrolet Corvette Forum Discussion

 

That thread is about transmission problems. This thread is about the Auto Fuel Management (8 cyl to 4 Cyl) system causing Engine valve train problems.

 

Aren't the non-safety-related recalls voluntary?

Consider the distinction between "probably of failure" vs. "rate of failure on my vehicle". The two of you could both be right, but talking about different things.

 

GM Lifter Recall Needed, Says Class Action Lawsuit | CarComplaints.com

 

Thanks, Blackcherry20, for that link!

Here are the contents:
December 20, 2021 — A GM lifter recall should allegedly be ordered for Buick, Cadillac, Chevrolet and GMC vehicles equipped with 5.3L, 6.0L or 6.2L V8 engines. Nine plaintiffs filed the General Motors class action lawsuit which alleges the valve train systems, active fuel management lifters and dynamic fuel management lifters are defective. A GM lifter recall has not been issued, but the plaintiffs claim that's what GM should do for owners of these vehicles.

• 2014-present Cadillac Escalade
• 2016-2019 Cadillac CTS-V
• 2014-present Chevrolet Silverado
• 2014-present Chevrolet Silverado 1500
• 2014-2019 Chevrolet Corvette
• 2014-2016 Chevrolet Avalanche
• 2014-present Chevrolet Suburban
• 2014-present Chevrolet Tahoe
• 2016-present Chevrolet Camaro
• 2014-present Chevrolet Camaro SS
• 2014-2016 Chevrolet Corvette
• 2014 to present GMC Sierra
• 2014 to present GMC Sierra 1500
• 2014-present GMC Yukon
• 2014-present Yukon XL

According to the lifter class action, the valve train system is comprised of software run by the engine control module (ECM), specially designed and manufactured lifters and other valve train components such as the valve lifter oil manifold.

The valve train systems control some or all of the 16 lifters to prevent certain valves to the engine’s eight cylinders from opening at certain times and allowing fuel to enter.

This means some of the eight cylinders will not consume fuel when the ECM determines only partial engine power is needed, such as during highway cruising speeds.

But the GM class action lawsuit alleges the lifters malfunction and prematurely fail because of multiple reasons.

The lifters (including the locking pin) allegedly do not conform to design specifications, are installed in an incorrect position in the lifter guide and/or are made of sub-standard materials.

GM also allegedly didn't consider the expansion and contraction rates of the lifters and the engine block, and the bores in which the lifters are inserted have widths that allegedly do not allow for the necessary clearance of the lifter to move freely, which damages the lifters.

A GM lifter recall should also allegedly be ordered because the automaker allegedly "failed to account for the amount of increased pressure to which the AFM lifters are exposed by the pressurized oil used to operate the lifters, causing them to fail prematurely."

The plaintiffs further claim more valve train maintenance is needed, more than is advised in GM's maintenance guides.

This allegedly includes, "more frequent oil changes, engine flushing and cleaning and/or replacing the valve lifter oil manifold and its filter at regular intervals."

According to the class action lawsuit, GM allegedly replaces the defective parts with equally defective parts that continue to fail and cause a ticking noise from the engine. Additionally, the lifter problems can cause the vehicle to lose power, "hesitate, and the engine can misfire, stall, shudder, stutter, or surge."

Although a GM lifter recall hasn't been issued, the automaker does have a policy to provide extended warranties, called Component Coverage, when vehicle owners have had two or more repairs at dealerships of the valve train and lifter problems.

The Component Coverage extended warranty covers "all internally lubricated parts, electrical components, control modules, blocks, heads, shafts, and torque converters, among other items for defects related to materials and workmanship."

However, the lifter class action says the extended warranty is only provided if a customer has already had their vehicle repaired twice.

The GM lifter class action lawsuit was filed by these plaintiffs:

• Danny Harrison — Alabama — 2021 GMC Sierra 1500
• Christopher McClave — Connecticut —2021 GMC Yukon
• Melissa Luster — Florida —2017 Cadillac Escalade
• Leon Jordan — Georgia —2015 Cadillac Escalade
• Daniel Demarest — New Jersey — 2019 Chevrolet Silverado 1500
• Mark Hayford — Ohio — 2016 Chevrolet Silverado 1500
• Ronald and Marilyn Jett — Texas — 2017 GMC Sierra
• Rebecca Prosser — Washington — 2021 GMC Yukon

The GM lifter class action lawsuit was filed in the U.S. District Court for the Eastern District of Michigan: Harrison, et al., v. General Motors LLC.

The plaintiffs are represented by the Miller Law Firm, P.C., Berger Montague, Capstone Law APC, and Gordon & Partners, P.A.

 

Define "repaired twice". Do you mean I have to have 2 lifter failures which might be 2 engine replacement jobs before GM does something?

 

"Define "repaired twice". Do you mean I have to have 2 lifter failures which might be 2 engine replacement jobs before GM does something?"

Good question. But that would be typical of the big 3.


The information in that article is from 2021.
if someone has the time, or inclination, to see what current status is, that may be helpful.
If it is dead, then there is no point in even talking about it is there?

 

You're confusing a Recall issued by NHTSA versus an FSA (automakers have various names for them sometimes). An FSA is a voluntary notification. NHTSA can force a recall for anything that violates statue. Technically things that constantly break down are "unsafe" or can "violate regulation" and therefore violate statute. I put "unsafe" and "violate regulation" in quotes because the pattern of defect of something has to cause a regulatory or safety issue.

 

This thread is about the incidence of the problem and therefore this article is relevant because, if the problem was very rare, GM would be more likely to just cover the cost of repair the first time instead of wait until it happens to a customer a third time. By the way, based on recent political news, 2021 is not that long ago in legal terms and GM is probably employing every possible delay tactic.

Besides that, whether the lawsuit is dead or not, the article contains a lot of interesting technical details about the problem.

Edit: I just called one of the listed law firms and the receptionist believes that lawsuit is still active. She said someone will contact me to confirm or not but I doubt if I will hear from them.

 

Well done @DugT

 

I get that - like on a motorcycle, engine seizure can result in wheel locking and crashing. But how is the AFM failures usafe or statue violation? I suppose "loss of motive power" might be, if I squint really hard and consider getting rear ended.

 

Could cause catastrophic engine failure leading to loss of vehicle control increasing the likelihood of a crash.

Which is likely exactly how they would word it.