How can I fix my Indesit WIDL 126 washer dryer?

My machine made a clunking noise constantly through one wash suddenly - as if trying to pump or fill water through a pipe on and off. Then the water did not drain away so I turned it off, unplugged, turned back on and did an rinse and spin cycle. That had fixed the glitch I thought...
The next wash it was fine.
The next wash it clunked along again (as if it was straining with a pipe or a pump) and then just stopped while its led lights flashed rapidly.
I unplugged and waited then started it again - it went to the end of the wash.
What can I check to see why it is playing up? Could it be a water pump of some kind? Could it be a collecting chamber that is blocking something that needs cleaning? I cannot find any instructions on the web or any diagrams!
Are you able to help please?
Thanks :o)