Noisy PS pump on Cayenne...

[Munter]

Due to being the font of all car knowledge in the office I've been asked by the Sales Director what it means when there's a lot of noise when the steering is at full lock.

Now he's had the thing almost 4 years, so I assume it's not always been like that. And I assume it's the power steering pump.

I've suggested he:
A)Stop using full lock for the moment
and
B)Consider what type of warranty might be covering such items and think about buying it
also
C)Find a good Porsche indy near Taunton or York

Assuming it is the PS pump do they hang on for a while or is it about to kill him.... .... and any hints on best place to take it if it's the latter?

[Rockster]

Munter said:

Due to being the font of all car knowledge in the office I've been asked by the Sales Director what it means when there's a lot of noise when the steering is at full lock.

Now he's had the thing almost 4 years, so I assume it's not always been like that. And I assume it's the power steering pump.

I've suggested he:
A)Stop using full lock for the moment
and
B)Consider what type of warranty might be covering such items and think about buying it
also
C)Find a good Porsche indy near Taunton or York

Assuming it is the PS pump do they hang on for a while or is it about to kill him.... .... and any hints on best place to take it if it's the latter?

The system experiences max pressure at full lock. I've been told it is not a good thing to turn the steering wheel full lock and leave it there for any length of time.

The system can be a bit noisy, but it is impossible to know if this is just from being at full lock or if there's something going wrong.

A test that one can do that sometimes helps determine if there's a problem is after driving the car a while to warm everything up to then someplace safe make a slow speed u-turn and after the turn release the steering wheel. Note at which position steering wheel stops. Repeat this u-turn operation in both directions several times and if the wheel does not stop at the same place each time this can be a sign the power steering system (the rack) is going out.

But before one does the above, I assume the power steering fluid level is ok?

If the fluid is low this can be a sign that the pressure relief valve in the power steering line has failed and the power steering rack sees higher than normal pressure. This over time can force fluid past the rack seals. The fluid is trapped by the rubber dust boots at each end of the rack so there may not be any signs fo a fluid leak. But one or both boots can feel like there's fluid in them when squeezed. I watched a tech remove a boot and the thing let go with a 'pop' and gushed some fluid out onto the work bench.

If this has happened the rack, the hydraulic line with the valve, and even the power steering pump will have to be replaced. The pump is damaged from running low on fluid.

My advice is the vehicle needs to be checked by a qualified tech to determine if the noise is normal and if it is then for the driver to resist turning the wheel at full lock and leaving it any longer than necessary. If the noise is not normal then that is a sign something is amiss and the tech will know what do next.

Sincerely,

Rockster.

[Munter]

Thanks Rockster