Hi all, hopefully someone on here will e able to give me a bit of advice, I am at my wits end.......

for about 6 months I have thought that my power steering pump was on its way out, making a grumbling noise on and off at tick over revs, making a god awful noise when locking the steering over again at low revs.
About 4 weeks ago, the tensioner gave up and threw the belt up, snapping the belt. I now think the noise I thought was the pump was the tensioner deteriorating over time.
I managed to get a used pump and tensioner (complete assy) so fitted that with the new belt only to find the tensioner was also on its way out. A week later I put a whole new complete assy tensioner on (non original). A few days later it started to make a racket again. To look at the tensioner wheel when the car is ticking over it is jumping about. I therefore thought it was a dodgy tensioner and told the supplier who sent me a replacement f.o.c.
I have today put the new tensioner (full assy) on and the piston locked and wouldn't spring back so took it all off again. When I twisted the piston it released. I made a decision then to put the original tensioner wheel with the 2 week old piston and put it all back together and it now sounds worse than ever.
I am now planning on replacing the original power steering pump tomorrow and putting the new tensioner assy on it which is the one that seemed to lock up today.
I am at witts end with this now and am trying to sell the car too. People are put off at the racket it is making which is not what I want.
Any help, advise, past experiences etc more than welcome

Thanks in advance.