Mine, it did little to nothing about the de-cel popping. But changing the exhaust gaskets and a proper re-seal of the pipes & flanges did. Removing all that smog crap reduces a few lbs. wt., cleans up the top of the engine as far as looks and running dressy LED lights to highlight the top of the engine, and it has to be removed anyway when doing a valve adjustment.I've looked at the de-smogging videos but most of them say all it does is stop the popping sound. Mine doesn't do that. Yeah I've checked and cleaned the throttle body and I use the factory honda air filter.