BMW Repair Questions? Ask a Mechanic for Answers ASAP
If the garage have checked all the external swivels and joints as mentioned before, then the problem sounds as though it may be in the steering system itself, these are particularly expensive units and I am presuming yours is the type with an assisting electric motor on the valve housing of the power steering rack. It is possibly this motor which is failing.
This company may be able to advise on if a re-build is possible and at what price.
I hope this help, but do ask any further details if needed.
The job time for replacing the rack is 2.9 hours and the tracking will then need to be reset. I have attached a list of the details.
The time taken overall depends on if the garage are going to send your unit for repair or fit a replacement unit, the replacement will be quicker but sending your unit for repair should be more economical.