On full lock, the Power Steering occasionally (and very briefly) gets heavy, before returning to normal. Notice this sometimes when parking up, I briefly get resistance through the steering, though it does then immediately return to normal. At the moment I have felt nothing in normal driving. There are no groans / noises from the PAS (as I used to get on my old Saab 9-5). No leaks that I'm aware of.

I did get my local independent to check the Power Steering when it was in for a service the other week, but they found nothing. (Not sure how hard they looked though).

It's a 2005 PD130 Superb with approx 85000 miles.

Any ideas?

Is it still on its original battery? Could simply be that it can't keep up with the 60A draw from the PAS pump anymore.

If it doesn't do it with a little throttle applied (go steady on the clutch!) then it's quite likely the battery's worn out...

HTH

It is on the original battery. I'll give that a try. Thanks.

The PAS pump is mechanically driven on the B5.5 - the battery has nothing to do with it.

Your problem is probably the one way clutch in the alternator pulley seizing intermittently, causing torsional oscillation in the aux drive. 85k is about as long as they last - replacements from GSF but you need a couple of special tools to fit it.

rotodiesel.

Miine has done this if I've tried to go in and out of full lock too quickly... As have many cars I've driven with PAS. I wouldn't worry about it. I try to avoid full lock anyway as it puts a lot of stress on the system.

Thanks for that roto. Would I just look to getting the alternator pulley replaced (is the one way clutch and the alternator pulley one item)? I'm not mechanically minded so no idea what this is, so sorry for the daft question.

Is this an expensive item / job?

That rang a bell about the alternator pulley - I'm sure I would have asked the garage to change this when the cambelt was done. One of rotodiesels recommendations here. I'll check my invoices to see if they have done it. (I've asked them to do stuff before and they haven't - e.g. water ingress fix).

also had this on mine now and again, but as it has no effect on normal everyday driving ( just tight parking occasionally ) thought id save my pennies till it starts getting worse or playing up a bit more then get it it sorted

Edited 17 March, 201016 yr by cavessuperb

If you neglect this problem, you will end up paying for a belt tensioner assembly as well as an alternator pulley. Check the pulley - it's easy enough to do.

rotodiesel.

just out of interest, how do you check the pulley, what feature is the one to look out for. Mine just turns a bit hard when approaching full lock so thought best to check this. Thanks

Put a small screwdriver through the front slots of the alternator (engine stopped, of course) and carefully engage a fan blade - the alternator has a very small internal fan on the end of the rotor.

Being extremely careful not to damage the stator windings, check that you can rotate the blades clockwise as you look at it but not anticlock. For a more thorough check, slip off the drive belt and twist the pulley sharply by hand. The rotor inertia will cause the clutch to disengage when the pulley is rotated anticlock and you will feel this easily. Check that the disengaged rotation is smooth and the pulley locks immediately when turned clockwise.

rotodiesel.

Put a small screwdriver through the front slots of the alternator (engine stopped, of course) and carefully engage a fan blade - the alternator has a very small internal fan on the end of the rotor.

Being extremely careful not to damage the stator windings, check that you can rotate the blades clockwise as you look at it but not anticlock. For a more thorough check, slip off the drive belt and twist the pulley sharply by hand. The rotor inertia will cause the clutch to disengage when the pulley is rotated anticlock and you will feel this easily. Check that the disengaged rotation is smooth and the pulley locks immediately when turned clockwise.

rotodiesel.

Thanks rotodiesel! Will do.