taylosw

do you recommend getting the thing to never allow it to go into v4 mode ? Afm disable or whatever it's called

Silberschnell

I think my C7 1LT spends too much time in V4 mode; on a recent 600mi trip, the computer said I got 31.1 mpg! I will use the paddles until I get the diabler!

djnice

The Range afm disabler works good and makes the trans shift better. Less hesitation, etc. However, if your using Range it is best if you know how to clear trouble codes. It will throw codes occasionally. When this happens you can unplug the Range and shut off and restart the car. This will get the car out of limp mode, but it will not clear the codes. Before going to the dealer for service I would clear the codes so they don't get side tracked.

taylosw

Is there a trick to resetting codes ? I am so new to cars and the z06.. i'm a bit scared haha

NSC5

Even in full V8 mode you will get very good mileage with your Stingray. My first long trip in my Z06 last year returned a trip average of 26.3 and that included two runs on the Tail of the Dragon and a lot of mountain driving in the park. Otherwise it was mostly 75-80 MPH interstate driving and that was running only in V8 mode with the additional air and rolling resistance of the Z06 and its less fuel efficient LT-4 engine.

I expect in a Corvette the mileage difference between a LT1 with AFM capability and a LT1 without the AFM hardware and restrictions imposed by the system would be insignificant. VVT operation and maximum RPM are constrained by the special push rods needed for the cylinders that shut off in V4 mode and the steel torque tube and additional AFM hardware add more weight and complexity to the engine. So the LT1 isn't fully optimized for V8 operation given that it has to also work in V4 mode. What works well for a brick shaped pickup or SUV doesn't necessarily have the same efficiency gain with a platform that is already highly fuel efficient. One of the great quotes from Jurassic Park, "Your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should" is applicable to many things and AFM, in particular using the torque converter to cover up some of the undesired artifacts of this mode, fit with this thought from author Michael Crichton.

NSC5

The current version of the Range will reset the codes by "hot" plugging it (inserting it with the car already running). You can also use a code reader and I always put my code reader in whichever vehicle I take on a trip; it is about as needed in a modern vehicle as the jack and spare tire were in older vehicles.

Bill Dearborn

If it is an M7 I don't think you have a thing to worry about. In the grand scheme of things there are some transmission problems with some of the A8s. It doesn't seem like there is a huge issue though.

Bill

lakemg

When mine is in V4 mode, it does making some pinging type noises but it is not the same pinging found in low octane/high compression situations. I'm wondering if you're hearing that and associating the sound with pinging from predetonation.

On edit: You should try to ride in another C7 in V4 mode to see if you hear it in their car. You don't note where you live, but if you're local to the Cincy area, shoot me a PM.

Silberschnell

Yes, it is possible I'm misinterpreting the sound. I experienced pinging in a '93 Porsche only under full throttle, but with the C7 the pinging sound is in V4 only at low rpms under light throttle. The dealer said no codes were triggered, and that if damaging detonation occurred it would trigger them. Will try to ride in another C7 when get the opportunity. Many thanks.

djnice

That's a good point that I wasn't aware of. I have V8.1R1. I am not sure I tried it with the car running. One way or another what mine did was deleted the codes causing limp mode, but there were still related codes read and rest later using Torque.

There are variety of code readers. I use the phone application called Torque. You have to buy a ELM327 WiFi OBD2 interface.
https://www.walmart.com/ip/ELM327-Wi...&wl13=&veh=sem
Then you plug it in the OBD2 port and connect it to Torque on your phone. You choose to read codes then choose to clear codes.

taylosw

Damn.. I have a lot to learn.. I have an A8 Z06 that I am going to pick up soon... guess I need to order this and a few other things.. lol

djnice

You can probably just drive it, have fun, and not worry about all this. It's likely the V4 mode won't be an issue for you and if it is you have warranty. I just don't like having warranty work done because of the hassle, not knowing how the car is being treated, etc.

Silberschnell

you are absolutely right - should just enjoy driving it- and I will! (although will use paddle shifters more often).

RKCRLR

I had a clicking sound. Took it to the dealer and was told it was normal. It got worse to the point it sounded like detonation/pre-ignition under light throttle. It would only happen in V4 mode. Returned to the dealer and insisted something was wrong. They took a test drive and agreed. Turned out to be the belt tensioner. They replaced the tensioner and the sound is gone.

flynhi

My 2015 Stingray A8 has a bad shudder in E mode, V4 at 1400 RPM. I have read through many posts on this so there must be a Tech Service Bulletin out on this.
Does anyone know aboutTechnical Service Bulletins for belt tensioner problems and V4 shudder / rattling?

Tks

383vett

You might get a better response starting a new thread. There are 2 options, the belt tensioner and the triple flush procedure of the transmission which can help the v4 issue.

Bubba144

The Range Technology AFM Disabler solves the problem. I purchased and installed last week to address the problem. Been driving/testing everyday with excellent results.

Bubba144

I had shuttering as well. The "triple flush" with the new Mobil 1 transmission fluuid solved that issue.

miss my Z06

So my question is - On a Z51 2016 Corvette manual trans, if you never put the car in Eco mode does the 4 cly activation come on at all ???

Elk

Four cylinder mode will never activate on a manual unless it is put into Eco mode.