So when I start my car after sitting for a couple of days the rear top air vent (fan area) sounds like somebody on a respirator (heavy breathing) anybody else have this? Could it be some type of vacuum leak? Car runs strong but does have a little bit of hesitation @ 3000 when driving easy (not often)

 

can't help you with the heavy breathing stuff ( that's the good news ) but the hesitations at/near 3k for me, usually signal a maf that is about to fail. or sometimes dirty injectors. try a techron injector treatment for a few bucks but wait until just before an oil change as it can leave some residue as it morphs into some other chemical compositon(?). if that helps, your fuel system may need some attention. mafs are cheap now too, if you buy refurbs. but i may be the only guy still has recurring maf problems on his 996t. i blame my tune + driving style. peg rev limiter, more often than i'd like. i bet if you maf and injector clean you'll only have the heavy breathing left to deal with. GL w it.

 

...don't understand why folks say the MAF is going...it either works or doesn't. There is a vario cam hesitation, usually at 2500-3000...normal. What DVs do you have?....sometimes those sounds are related to the DVs. Which is essentially a vacuum leak.

 

really? i've always had that, but it goes away (?!) when i replace the maf. so it's the cam hesitation. ok. i read that recently.. similar to the startup dip 3 secs after startup hesitation? i don't have breathing or honking so my dv's are fine lol

 

[QUOTE=wross996tt;9860363]...don't understand why folks say the MAF is going...it either works or doesn't. There is a vario cam hesitation, usually at 2500-3000...normal. What DVs do you have?....sometimes those sounds are related to the DVs. Which is essentially a vacuum leak.

I believe they are after market not sure who's? Sounds like where the noise is coming from.

 

failing stock dv's is a fairly distinct "honking" kind of sound.