Vauxhall Astra 2005 windscreen wiper problem

[MDian]

For some reason the windscreen wipers on my Astra run-about are not working correctly. A while ago they slowed down quite a lot but some WD40 on the joints appeared to have resolved. However, now when I switch to the first 'intermediate' setting the windscreen wipers only do a quarter rotation, then a further quarter rotation a few seconds later, and so on. If I switch to setting 2 or 3, it is constant but slow, but at least doesn't pause ever quarter!

Any ideas what the problem may be? Motor for the wipers possibly, or fuse? The rear one seems ok.

[MDian]

Any ideas guys before I have to start pulling stuff apart and doing more harm than good