whine noise at startup

[uimtiaz]

Hi again,

Everytime I start my 99 c2 996, i get this whiny noise that goes away after about 30 seconds. any ideas. No warnig lights come on in the instrument cluster. Any ideas??

thanks

Umar

Ps: Loren this site is ridiculous

[GaryFB]

PS to Loren, I think the site is GREAT!

The electric air pump that injects air into the exhaust system operates for approximately 30 seconds when the car is started cold. I am sure you are hearing the electric air pump. Do you think the noise is getting louder?

[uimtiaz]

thanks gary

the noise is consistent. not getting louder.

Do you think this noise is a problem or just normal sounds.

Anyway to make it stop

umar

[Orient Express]

thanks gary

the noise is consistent. not getting louder.

Do you think this noise is a problem or just normal sounds.

Anyway to make it stop

umar

<{POST_SNAPBACK}>

these air injection pumps are used in several german cars incuding audi and VW. They tend wear the motor bearing a little, which causes the high pitched whine. no biggie, just the bearing balls resonating against the bearing race.

In rare cases something like a leaf or other material gets sucked in and lodged in the blower case which rubs against the squirrel cage fan. eventually it will work itself out.

[Mitty]

Curious:

What would happen if I disconnected it? CEL? Bad for engine? Rough engine until warm?

-Darren

[Loren]

Curious:

What would happen if I disconnected it? CEL? Bad for engine? Rough engine until warm?

-Darren

If you disconnect it for any period of time you will get a CEL. The air pump is there for emissions. In California the state required smog test will actually test your air pump to make sure it hasn't been disconnected and is working.