Sorry this is long but I want to include as much information as possible - looking for some advice/recommendations for where to go with our picasso which is having problems with the power steering (seems to be a common thing reading up).

Wednesday 20th April
10 year service - New Timing Belt, Antifreeze, Oil Change and MOT. Not sure it's relevant but for completeness.

Thursday 28th April
Steering suddenly goes exceptionally heavy when turning, improvement is seen at high revs but parking is a total nightmare - even half a turn on the steering wheel is difficult but feels looser once you get past that point. Father in law says the car is making a strange high pitched noise on reversing at full lock (not heard this directly).

Friday 29th April
Garage flush power steering system which shows an improvement. They recommend replacement of steering pump saying it seems to have gone weak, can't get the part till the following week. Unsure how long the system will remain improved but we were away the following week plus it was bank holiday weekend so had little choice but to crack on with the car as it was - garage assure us driving it if it recurs isn't going to damage the system further.

Friday 6th May
Drove 80 miles on our trip and around and about for 4 days - it was slightly heavier than previously but no major issues. On the way home it starts to act up again. Following day steering is really heavy again so we book in for the pump to be replaced the following week.

Tuesday 10th May
Steering pump is replaced and seems fine on testing. Collect car following morning and seems lighter than ever - can turn the wheel with one finger and it feels feather light. Delighted that it's resolved and carry on using car as normal (very light use).

Friday 13th May
Take car on a 30 mile round trip. On the way the steering starts to feel heavy again and by the time we arrive it's back as bad as it was on the first day the issue started. Car is only possible to park by wrestling the steering wheel around. Let the garage know the problem is still ongoing and arrange to take it in on Monday. Parked it for the weekend for fear of damaging anything further.

Monday 16th May
Garage collect car, test 3 times - can't replicate issue. Suggest it might be because it's a warm day but also say it was fine from driving off, ask to keep car for another day to see if they can replicate it in the morning.

Tuesday 17th May
Garage managed to replicate issue. Remove and refit, still happening. Replace old pump, still happening. Conclusion - likely to be the rack rather than the pump causing an issue. Order in a new rack to fit the following day.

Wednesday 18th April - Thursday 19th April
Garage fit rack with old pump, still having intermittent issues. Refit new pump - still happening. End up stripping everything back and starting again. Say that the pump replacement now seems to have resolved the issue but leave both new parts in the car - they can't return the rack and figure we may as well have them both regardless (no charge for the rack or many hours of additional labour - very thankful for that!).

Friday 20th April - Current
Car is returned, short test drives over the weekend indicate behaviour is different, improved but still not right. Steering is still going intermittently heavy on corners and weighting is fluctuating seemingly randomly. Revving engine no longer frees up the steering (which it did before the pump was replaced). Reverse seems to make it lighter.

So now we're not sure where to go with it. Some research indicates that the pressure switch, UJ or steering knuckle might be the next port of call? Neither of these things mean much to me if I'm honest - I'm a technical person but not great with cars. I guess I need to check what the garage have tried exactly come Monday but in the meantime I'm trying to increase my knowledge so I can have a more useful conversation on the day.

Again - apologies for the length of my post. Any ideas or suggestions very gratefully received. Thanks in advance.