formula80_ca

"Unbolt it, put a few washers, and install it back. This isolated the part enough to keep it from breaking down."

Hmmm do you have more info on this?
... I wonder if I can convince the GM tech to do this before he puts my car back together again.

X25

I think @BaylorCorvette can help you out with the details.

BaylorCorvette

I unbolted the actuators, got a bunch of washers from Home Depot to create a heat sink and longer bolts to account for the washers. I stacked about 4-6 washers (cannot remember since I did this a couple years ago) per bolt. It creates enough gap where the actuator is able to be bolted to the exhaust but the valve doesn't actually make contact, basically making it non functional. However (knock on wood), I've been running for over two years now like this with over 1k track miles and zero failures or issues since.

Sebring Bill

AFM Update. Did a track day Saturday at NCM. Very warm day of up to 95 degrees. I was hoping that removing the center air dam would help, but the CEL came on during the second session during the morning before I got off the track. AFM valves clacking upon each startup there after. I run the car in full auto mode and I think the transmission shifts about perfectly in track Sport 1 mode. Other than this AFM problem I think the car is incredible. BTW was able to get a PR of 2:21:4 during the day. Scheduled the GS in for AFM service and suggested the BaylorCorvette washer solution to the dealership.

raylo

Great idea! Maybe even use a couple layers of fiber washers or make some from gasket material to act as an insulator.

Joshua Dritz

Hi all. I have a 19 grand sport with the 8 speed automatic. I had the AFM actuator valve issue this past Saturday at Mid-Ohio during my last session. It was a 30 minute session that directly followed a 20 minute session. So probably 40 out of 50 minutes on track. Came off track to the clicking noise, used my ODBII reader to figure out what was up. It was the car's fourth track event and it wasn't a very warm day. In any case, it has the CEL on and all of the codes referenced in this thread. Is there a TSB on this or new parts? It's going in tomorrow for service so I am just interested in how to provide guidance to the technicians. If not, I'll go the washers route after the dealer replaces them.

Sebring Bill

I have a 18 GS with the auto. As of two weeks ago I was told that there is no solution or parts changes. I believe that my AFM Valves have now been replaced 8 times, yes 8, under warranty. 2 of those times were from running at Mid-Ohio by the way. As you get familiar with tracking the GS I believe these will go out every single track day. Most always in the second session of the morning. If I had this to do over, I would have went with the washer solution or Z06 pipes with the vales fastened up much sooner. Also note that the computer must learn the new valves while they are in the pipes before taking them out. Hoping to get back to Mid-Ohio as well, before long. Good luck

Oh4GTO

I went the Z06 cat back route with my GS. I tied the valves out of the way and check them every now and then. No issues after 8 months.

turboffr

Remove them and have them tuned out. Problem solved. I just tuned them out on a 2017 GS yesterday.

Wiscovette

For all you auto guys and gals that melted your afm valves, did your car not allow to enter manual mode after you melted to module? I’m fairly certain I’ve melted mine and the car won’t enter manual mode now.

formula80_ca

I have a 2015 Z51 and had both of mine replaced, one side twice, but have never experienced being locked out of manual mode on my 8spd auto.

NMyGS

I have a 2017 A8 Grand Sport and a couple of weeks ago I melted the afm actuators at the track. I ordered new actuators and tried adding the washers that BaylorCorvette suggested. When I did, I got new error codes P12F1, P12FE, P12F0, P12FD about Cylinder Deactivation Exhaust Flow Valve Position Not Learned. I took the washers out and everything appears to be ok. The CEL hasn't resurfaced.

Ughhh...This is so frustrating. I love this car. I love the way it sounds. I love the way it handles. It is so much fun to drive but if I can't take it to the track then it is almost worthless to me. It's like having a hot wife and only being able to kiss her. I am so disappointed GM doesn't have a fix for this. Anybody want to buy a 2017 Grand Sport with about 8000 miles on it?

That's my 2 cents.

formula80_ca

I just had to replace (lucky under my extended warranty) the passenger side AFM actuator for the second time.

My local dealer service manager is very good to deal with and agreed to do the washer fix on the drivers side the last time it went 1/2 a year ago (second time for that one too). Some codes appeared just days after that fix. Knowing I would likely burn up the other side at the track we decided to wait until that happen to deal with it.

So this time when i discussed fixing the passenger side using the washer fix with the technician he came up with another solution... Remove the metal disc on the actuator that turns the exhaust flap. Using washers moves that disc up away from turning the flap so it is the same end result. The heat from the exhaust doesn't transfer to the metal disc on the actuator which burns out the turning / sensing mechanism. So with the service manager agreeing to try this that's what we did. The learn code issues you experienced came up (because it was a new unit) so they put the disc back on, went through the learn process then took the disc off again and now it works with no codes. So they did the same thing to the other side.

Time will tell if this fix works for track use... Fingers crossed. I have one year left on my extended warranty.

ErnieN85

Take them out and tune the codes out

BostonVette

I think your issue was that you didn't allow the actuator to learn the valve limit points at open and closed position.
Since they are know "educated", you can probably go back to the washer setup and not throw a code.

NMyGS

BostonVette, I am glad you mentioned that because I had been wondering if that was the case. I also saw where AWE has AFM Valve Simulators you can install on the actuators that have limiters on them. I would just need to find a spot to tie the actuators off.

I only have a few weeks until the weather gets too cold for the Pilot Super Sports. At that point I am going to open her back up and try the washers again, and if that doesn't work I will try the AWE simulators. I'll be sure to post my results.

Bill Barcellona

I have a 2019 Grand Sport and experienced the same problem after a track session at Laguna Seca on Labor Day. Track mode PTM sport 1, with approximately three 20 minute sessions. The exhaust makes a horrendous clacking racket. I’m taking it into the local dealer tomorrow. I hope this is a warranty issue.

X25

Unfortunately, they did not remove it on A8 GS/Z51 cars (but it's removed on all track-oriented M7 Corvettes 2017+; Z06+ never had it IIRC). Once it is replaced under warranty, you should look for a solution (this is what I did to my Z51 to pre-emptively fix it)

ErnieN85

If you intend on track time it is the way to go

BostonVette

Hello guys
This is a question for those who have used the spacer method for preventing the actuator meltdown.
Do any of you recall what size bolt and it's length is in the stock setup?

My dealer is willing to install the hardware to space them out when the new ones get replaced.
I want to make it simple and easy for them by getting a set of appropriate length spacers and longer bolts so it goes smoothly.

I'm guessing a 1/2" spacer should do it, right?

Thank you