Hi
The other day I used the rear window wiper in the rain for the first time on my Polo Trendline.
It made this annoying noise as it jumped and stuttered across the window. So my first question is, has anyone else had this experience?

I contacted the VW dealership and had their technician look at it. He said he cleaned the rubber on the wiper and topped up the washer fluid with Windscreen Cleaner Concentrate.

What I don't understand is, why would topping up the washer fluid stop the stuttering and noise? I'm not supposed to constantly spray the washer while the wiper is on, am I? Also, wipers are used in the rain, so any washer fluid acting as lubricant would be washed away anyway, wouldn't it? Or am I missing something?

Are there people who've had the stuttering wiper issue resolved by using Windscreen Cleaner Concentrate?

Thanks in advance for any insights.
Goz