I have a 1999 GTP with the 3800 S/C engine. It starts just fine and I can drive around all I want and all is good until I take the RPM above 4000. Then the engine will start chugging. It feels like it may be dropping cylinders like a rev limiter kicking in. It will do this if I am sitting in neutral or if I am driving down the road. It doesn't matter what gear the car is in. Anybody have any ideas?

Thanks

Jack

Sounds like a clogged catalytic converter.

Any check engine codes?

Under load sounds like a clogged cat.

I thought that's when the limeter kicks in at 4000 rpms, mine did the same thing, only stiing though, don't think i had mine up to 4000 rpm driving.

That tells me cat

Thanks guy's,
I will check it out this weekend.

Jack