Cavitation from power steering pump?

[TimS996]

I've started getting a sound like cavitation at low speed when turning tightly, such as out of the drive or 90degrees plus. Has anyone else come across this! Car is an 06 with a full history. Is it likely to be low fluid or the pump failing?

[Quatrelle]

I'm sure someone will correct me if I'm wrong, but the Passat has electric power steering, so no fluid and no pump.

[TimS996]

I have to admit, if it has, I'd forgotten! Will check in the morning.

[Brycie]

Three of us with A6 C6's have had this recently (though I have to admit I have no idea what cavitation means lol). The common theme seems to be a sticking alternator pulley on the auxiliary/drive belt. Only £35ish + two hours Labour in my case, although I also bought a second hand power steering pump from eBay for £23 as I wasn't sure if it was just the pulley or the PAS pump. Problem is completely gone for all three of us (the other two guys only changed the alternator pulley & it fixed it though).

Solved Horrible noise on full lock while manoeuvring (http://www.vwaudiforum.co.uk/forum/showthread.php?155840-Horrible-noise-on-full-lock-while-manoeuvring&highlight=alternator+pulley)

Edit: just read Quattrelle's post & assuming he's right about the lack of a PAS pump on the Pass at, it would point to the alternator pulley being the culprit, so at least you won't have to change the PAS pump just to be thorough.

[zollaf]

cavitation is where a boats propeller stops being efficient and air bubbles form on it. this can lead to lack of power and also erosion of the prop, something to be avoided at all costs.
i would say its more likely to be the alternator pulley.

[TimS996]

Thanks. I'd been reading the American forums where there seemed to be a lot more on this problem and had come to a similar conclusion regarding this pulley. I'm going to phone my VW dealer and get the car in there ASAP before this becomes more expensive. Only problem is their £100 ph labour to fit £35 of parts.

[zollaf]

take it to an indy then.

[TimS996]

Just wanted to see what they would charge. Booked into an Indy next week to find out. Hopefully it's a cheap bit.

[zollaf]

an genuine INA is about 65 quids. you can test it easy enough. with the engine off, you should be able to turn the fan inside the alternator , using a small poky thing, screwdriver etc, in one direction but not the other.