After I removed mine, and used the dimpled plates, I still had the de-cel popping. When I later replaced the exhaust gaskets, that eliminated probably 90% of it. So if the gaskets aren't removed before re-installing the pipes, it'll happen again. They are a crush gasket, intended for 1 time only. They are very hard to see and not exactly easy to remove. But they're there. Many threads about this. If you run a fuel manager, such as PC III, the best settings are 2,0,0 with the 2 being richer down low just for that reason.