annoying streak mark on windscreen

[GrahamFR]

So ive never had this problem before as my Leon's had wipers that crossed over in the middle and its the main thing I miss apart from alcantara seats, but I digress. This streak is always there these days and no amount of cleaning with glass cleaner has an affect...


So how do I get rid of it?

[Booth11]

New wiper blades.  Bosch Aerotwin if you haven't got them already.

[GrahamFR]

So its the blades themselves? I thought it oil pushed up and building up in that one place, so I was thinking it could be cleaned by vinegar or some other light acid... Like its there when I wash the car, you can see it when you wipe across so changing the wipers means it'll still be there no?

[Booth11]

Yeah, you could try cleaning with vinegar first but if ithe build up is a result of poor, skippy wipers then it'll just build up again.  Worth a shot though.  Have you still got the oem wipers on?  Thought they were supposed to be dire.

Last time I cleaned my windscreen with vinegar it had bugger all effect. That was to try and stop oem Valeo wipers squeaking, juddering and streaking but it was only swapping out for aerotwins that resolved it.  That was over a year ago and problem free ever since.

When I get my R later this year, first thing I'll be doing is swapping the wipers for Bosch, closely followed by swapping the Bridgestones for conti 5ps 

[GrahamFR]

Yeah swapped them over about 8 months ago so they probably need replacing. Gonna try some vinegar at the weekend see how I get on but I expect it to have the same effect as window cleaner. Maybe I need something spirit based

[Booth11]

Give Methylated spirit a try and remember to also clean the wiper blades. 

Do you use any product on your windscreen?Maybe something excerbating the problem.  I'd give RainX a wide berth, imo it's the root of many wiper problems.  I don't use anything on my windscreen now, just gets washed weekly along with rest of car.  I wax all other windows but zero product on windscreen.

[GrahamFR]

Ha I threw my wipers in the bath a few months ago so it shouldn't be them. I have some rain x additive in the garage I was actually gonna give it a go but not used it on this car. Only window cleaner but obviously there is a bit of sealant over spray but I wipe it off. I think its off the road or the coffee factory we've been building, that sh!ts vicious even when air borne leaves a residue on the car

[Booth11]

Panel wipe (Gtechniq very good) or IPA for removing excess sealant and other similar residue. 

Have you tried claying the windscreen?  Should also be ok to use a tar/glue remover on glass.

Whatever you try, I'd still give the blades a good clean again, even if they have been previously bathed!   Whatever crap is on your windscreen will also be on your blades.

[Wo-Wo]

Try claying the glass too, could it be smeared tree sap or anything like that?

[GrahamFR]

My money is on coffee residue. I have some clay in the garage too so I'll give it a go thanks