E39 M5 power steering issue?

[JerseyS2000]

Hi all

I wonder if you can shed some light on a possible problem with my car.

On two separate occasions, I have switched on the sport mode when the car has been cold and a graunching/moaning noise has come from the steering wheel when applying lock, especially at low speeds. It feels like I'm working harder to turn the wheel at the same time ie more resistance and some light vibration.

I'm thinking that the power steering pump (or summat) may be on the blink, but the symptoms don't come back when the car has been stopped and then restarted a few hours later.

Any ideas? I've still got 6 months warranty remaining and will try to claim if so.

Many thanks

Ben

[Neil.D]

Simple but have you checked the power steering level?

[JerseyS2000]

Simple answer - no! But I will do.

Would that explain why it comes and goes though?

[Neil.D]

Possibly but who knows. I beleive it needs to be checked when cold BTW.

[JerseyS2000]

Interesting development. (well, i think so anyway)

A mechanic mate who used to own an M3 advised that you shouldn't switch to sport mode when the rev counter lights are still lit ie the engine is cold.

Anyone else heard of this?

[Neil.D]

Never, ever heard of that. What is his reasoning?

[JerseyS2000]

None given as such apart from you shouldn't rev the engine or press the sport button while the lights on the rev counter are still lit. He reckoned I should consult the manual to ensure that I don't do any other damage while the engine is still cold. How the hell does that affect the sport setting on the steering or the sensitivity of the throttle exactly?

Still confused!

[jim_1976]

JerseyS2000 said:

Interesting development. (well, i think so anyway)

A mechanic mate who used to own an M3 advised that you shouldn't switch to sport mode when the rev counter lights are still lit ie the engine is cold.

Anyone else heard of this?

It doesn't make a blind bit of difference! The only thing the sport button does on an M3 is alter the value that the electronic throttle sees from the electronic accelerator pedal. Because the pedal is a potentiometer, it just alters the resistance (in laymans terms, I'm sure someone will elaborate on this!). It doesn't make the car any faster, just makes the pedal more "sensitive" if you like.

[Neil.D]

JerseyS2000 said:

None given as such apart from you shouldn't rev the engine or press the sport button while the lights on the rev counter are still lit. He reckoned I should consult the manual to ensure that I don't do any other damage while the engine is still cold. How the hell does that affect the sport setting on the steering or the sensitivity of the throttle exactly?

Still confused!

I dont think you 'mechanic' mate is up to much, no offence.

As long as you don't over work the engine when cold you wont have any issues.

The 'sport' button does not put any more stress on the car. It just makes it annoying.