W212 owners- slight buzzing noise steering at full lock?

[derektrotter]

Hi All

I recently aquired a 2011 E250 saloon, everything seems fine with the car but I have noticed when the steering is at full lock, e.g. when parking, I can hear a slight buzzing noise, I dont recall hearing this on other cars, can other W212 owners confirm they also get this noise?

If everyone elses makes no noise at all then I may have to investigate further..

I assume its because the power steering pump is under more strain however also want to make sure its not a sign its on its way out or similar!

Thanks

 

[daveenty]

I would assume the same as yourself really.

Held against the stop, the fluid has nowhere to go. Is it OK when you back it off a fraction? If so, then don't worry about it and try not to force it against the stops as it won't do it any good.

 

[Peter DLM]

Every PAS car I've ever had does this. It's not actually a good thing to do for the pump, so I wind the lock off a degree or 3.

 

[MancMike]

All PAS cars do it. It's an attribute of the hydraulic steering rack + PAS pump. Just don't pull against it, as said if you relieve the tension slightly the sound goes, and you're still at the same steering angle, just not pulling against the stops.

 

[derektrotter]

Thank you all, yes the sound goes as soon as I turn a bit away from full lock so looks like its normal.

I guess as its a new car (to me) I'm a bit paranoid until I've had it a while