Originally Posted by pavo335
i thought the flapper was only closed on cold starts and once the engine warms up a little it is always open. When i start the car in the mornign yep nice and loud sitting in the drive (helps get the girls outa bed
) but half way to work sitting at lights quiet as stock???
pretty sure the flapper only opens on cold start and once warm only after certain RPM.
you should try a cold start with no cats and BMW PE... have to do the drive of shame out of my street lol..