BDW15 dishwasher?

Just moved house and inherited a BDW15 DW, everything working fine, then noticed an E4. Having read all the advise from others about moping up water inside the machine and at the back of the black panels, I have checked and there is no water to be seen, but still making a terrible noise. Any suggestions before calling an engineer, or buying a new machine.

Gill
February 2013