My GTP has been running good, but today I ran into an issue. If im in 1st gear and I step on it, she hits 6,000-6,100 rpm it stutters for a split second then shifts. Its almost seems as if its hitting a rev limiter, or fuel is being cut off. It doesn't sound like any rev limiter I have ever heard though. If I get on it but let off right before 6k it doesn't make the noise and shifts as it should. In the past when I've revved it up in neutral and held 4-5k I believe makes the same noise, a fuel cut off or something. I've ruled out the catalytic converter, because I don't have one. I've ruled out the plugs, because I changed them 2,000 miles ago. I'm thinking it could be wires, fuel filter, or possibly because I could never get the case relearn to perform correctly. My theory is with the cold weather and 180 t-stat I couldn't get the temp high enough. There's no loss in power or anything like that, besides the 6k cut out it runs flawlessly. I haven't had the opportunity to test the issue in 2nd gear. Can't do 80mph in town, ill give it a shot on some back roads tomorrow. I checked to make sure I didn't have and wires arcing on the manifold, I unhooked the positive and negative terminals, then held them together for 10 seconds, and double checked transmission fluid. It's not like transmission slip or anything, the motor definitely changes sound. What do you experts think it could be?