# Engine making some weird noises when cold...



## pendulum (Apr 29, 2001)

this just started, but.....
the last couple of days, when i cold-start my car, it sounds like there is a jet taking off under the hood.... either that or a vacuum cleaner on "hi". it is very loud and sounds very not-good. i've never heard this sound come out of an engine before. now, when the car is warm after driving for 5 minutes or so, it _completely_ goes away. this just started a couple of days ago. VAG-COM'd the car, nothing tripped, everything is "ok".
anyone know what this might be? i went under the hood and it sounded like it came from IN the engine (although admittedly i'm not the best troubleshooter). anyone had this issue before?


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## ps2375 (Aug 13, 2003)

*Re: Engine making some weird noises when cold... (BabyFoodYellowGTI)*

that sound is the Secondary Air Pump. You may have the hose from the airbox (suction side) off, or the pump could be going south. BTW, it only runs at a "cold" startup to aid in Cat light off.


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## pendulum (Apr 29, 2001)

*Re: Engine making some weird noises when cold... (ps2375)*

probably "going south" as i haven't messed with anything there.
this isn't catastrophic to anything is it? in other words, if i don't repair this, it won't grenade the rest of the engine will it? and thanks for the response!


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## ps2375 (Aug 13, 2003)

*Re: Engine making some weird noises when cold... (BabyFoodYellowGTI)*


_Quote, originally posted by *BabyFoodYellowGTI* »_this isn't catastrophic to anything is it? in other words, if i don't repair this, it won't grenade the rest of the engine will it?

nope, just for the cat light off. you will get a CEL due to SAI flow too low.


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## lonestar22 (Apr 14, 2008)

*Re: Engine making some weird noises when cold... (ps2375)*

mine sounds like that whenever the a/c is on, i can hear it while driving with the windows down if its quiet out


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## b5in (Sep 10, 2003)

*Re: Engine making some weird noises when cold... (lonestar22)*


_Quote, originally posted by *lonestar22* »_mine sounds like that whenever the a/c is on, i can hear it while driving with the windows down if its quiet out

is that normal, cause my car is the same exact way, it sounds like a storm warning horn, does it mean something is going out?


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