'97 328i Secondary Air Pump Noise

[lfein]

posted 05-07-2002 11:01 AM
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I isolated the noise to this secondary Air Pump (11 72 1 744 490). The noise is like an electric motor having trouble. It only makes the noise during warm-up. It has some clips on the side like it can be opened. While it makes the noise the engine seems to run OK. Before I buy a new one at $180, or open it try to open it, does anyone know if it can be repaired, or maybe there is something lodged in it somewhere.

[mark canales]

i had this problem with my 328i 97 also it only ocurred when cold (when the pump is needed) what happened is that the one way valve inside it became a two way valve and sucked in water thus damaging the the pump. fortunately it happened to mine while under warranty

[gavelez]

I have a 96 328i also, and I was told that the air pump noise is normal. It is basically a vacumm for the fuel line or something. the noise is normal to come up on startup.

[paulauma]

Actually, It's an emissions reduction piece. It blows (supposed to blow) air into the exhaust to reduce hydrocarbons at startup. Mine also filled with water so I guess the valce inside mine is shot too?