Just got in from a horrendous drive in Akoya from Maidenhead (my parents’) to home near Honiton, with a detour to Frome to pick up an excellent pepper pot alloy bagged off eBay for £25 (I now have two out of the four I need to make up a winter set, and I have a third located on Facebook marketplace in Ottery St Mary reserved). Total of about 200 miles mostly in rain coming down so thick the wiper was completely outwitted.
I couldn’t go faster than 50mph on the A303 at first - the wiper just seemed to smear the water on the screen rather than clearing it, so I cursed myself for not fitting a new genuine Audi wiper blade (I have two in stock, eBay bargains).
Stopping at Merryhill services for a coffee to steel my nerves, I had the idea to buy some bug and tar remover from the shop while the car was under the canopy and have a go with it to see if I could at least improve the performance of the wiper a little by cleaning it. Well the amount of black filth this stuff pulled off the wiper was amazing, I must have sprayed it and wiped it down at least a dozen times and each time the cloth had a thick black line.
When I was finally sure I had done a thorough job I set off again and my word, what an improvement! The effect was almost like replacing the blade - I can thoroughly recommend trying this to others if your blade is doing the same thing.