<I've noticed a noise (like a value opening and closing) just behind the central vents in the dash of my 94 318is.> I've noticed the same thing on my 93 318iS. I haven't noticed the pulsing though. It sounds like the motor on the air duct valve could be sticking, but at this point, I'd rather not have someone tearing apart my dash. Regards, Jeff 93 318iS 84 318i