E39 540i power steering....Bleed???

[Marko911/944]

So ever since I've owned this 540 the power steering has gotten very stiff at the strangest times. I know theres a joke here, but this is a drag. The assist is fine most of the time but gets way too tight suddenly while cornering. It seems like a bigger problem than just bleeding the system, but I dont know. Is it something like variable assist failing? Thanks.

[CPC]

You don't mention any noise, rattle, squeal or leaks on garage floor. So I would suggest Step 1) check fluid 2) check serpentine belt & tensioners 3) check for noise and position of ps pump ( lower support bracket tend to break) 4) from under engine compartment visually inspect pump for leaks. 5) check ps lines to ensure they are not crushed or kinked. It is possible that it insn't the pump, but start with simplest and highest probabilty (belt or pump). If it isn't the pump, will be much more work & $. Since it transient I suspect a slipping belt...

[CPC]

Ps. Our cars don't have variable assist

[Marko911/944]

Thanks for the reply CPC. No leaks no rattle no squeal in 8 years, but its always had this issue. Since the first test drive even.....never got better or worse. I will check the bracket and the ps lines. Great ideas, thanks.