If you don’t have the part number I think the only way to tell is to open up the exhaust and see if you have the flaps inside. You may be able to tell by opening up the actuators but I’m not sure. I have the ATAK (140678) with the simulators and threw a P121B for the passenger side. It wound up being the design of the simulator part of the exhaust that needed to be fixed. They had an updated version of that part of the exhaust that they sent me which fixed the issue.

It’s not hard to open the actuator up. You just need to make sure you put the spring back in the right way or you’re definitely going to throw a code. Check to see if anything is getting stuck or if the spring looks damaged at all. It could be that the actuator is spinning too much or not enough. If I had to guess though, it’s probably a similar problem to what I had.

 

It’s not hard to open the actuator up. You just need to make sure you put the spring back in the right way or you’re definitely going to throw a code. Check to see if anything is getting stuck or if the spring looks damaged at all. It could be that the actuator is spinning too much or not enough. If I had to guess though, it’s probably a similar problem to what I had.

Thanks for the response. I wasn't sure what I was in for by opening the actuator. Likely this is all I need—the knowledge that I probably won't ruin anything by opening it up.

 

Opened up both actuators and they seemed fine. Spring in the correct place, no apparent damage, valves feel like they open and close correctly.

I guess now I'll take it into the dealer while it's still under warranty, and reach out to Borla.