Whirring noise from an electric pump(?)

MikeTye · Post by **MikeTye** » Sun 15 Jul, 2012 21:57

My 2.0 Z3 has had this whirring noise that quite often comes on when I start the car, comes from what looks like it might be a vacuum pump or something? I'm used to my nice simple Peugeot Diesel engines!!
It goes off eventually but just wondering if they all make this noise? Kind of sounds like a bearing or something might be on it's way out or gone but just wanted to double check it's not meant to make that noise before I go replacing it...

Video of the noise... http://www.youtube.com/watch?v=YW97iZLHhRQ

gookah · Post by **gookah** » Sun 15 Jul, 2012 22:35

Its the secondary air pump that provides a boost of air into the exhaust to reduce emissions on startup.
Was fitted to adhere to American regulations across the range.
see this thread:
http://www.zroadster.net/forum/viewtopi ... hilit=+air

MY son's was making this noise,
It was making a very loud howling noise as the bearings were failing, So I have decided to blank off the diaphragm valve and then disconnect the supply at the bottom of the pump and tie it out of the way,
As follows:

first remove the diaphragm valve from the exhaust manifold:

then remove the gasket from the manifold:

then using the gasket as a template, I made a metal blanking plate:

Refit the gasket to the manifold, then the blanking plate on top and refit the valve and all hoses.

Then disconnect the airpump supply-cables from underneath, job done.
Air pump no longer operates, and althought the diaphragm valve will open and close as before, the exhaust gasses can not flow back beyond the blanking plate.And it still looks like its 'as original' build.
No MOT fail either.

Mike Fishwick · Post by **Mike Fishwick** » Mon 16 Jul, 2012 12:13

The air pump was a US requirement - the later models are not fitted with one.

Mike Fishwick · Post by **Mike Fishwick** » Mon 16 Jul, 2012 15:49

Don't forget about the ECU box cooling fan - it sucks and discharges via a small rubber nozzle just above the throttle pedal, and runs for a short while after the ignition is turned off.

MikeTye · Post by **MikeTye** » Mon 16 Jul, 2012 21:16

Thanks for your help, glad it's not just me that had this pestering them. Nice little job for the weekend then

zroadster.net

Whirring noise from an electric pump(?)

Whirring noise from an electric pump(?)

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