[DaveB]

Right then! Here's a brainteaser for you fellow Bimmer techies. It's only a niggle to me but it gets on my nerves.

Problem
When I activate the rear washer, the wiper starts immediately, followed eventually by the washer. My concern is that in the 2 seconds it took for the washer system to prime and spray the wiper has done 1 full cycle and effectively dry wiped the rear screen with all the grit that was on it - hence causing micro scratches that make wiper blades less effective at producing a streak free wipe.

I drove a friend's 2009 5 series Touring last week and when I hit the rear washer button on that the washer fired straight away hence the wiper was wiping a wetted screen from the start.

Challenge
Does anyone know if there's a difference between the 5 and 3 series systems?
Is there a way of either delaying the wiper from starting to give the washer a chance to prime itself or even speed up the priming of the washer so my car works like the 5 series?

I have a 2006 e91.

Many thanks in anticipation.

[HighlandPete]

I'll have to take a closer look at how mine works, but never felt it is slow to wet the rear screen. I'd say after using my car for almost 6-years it isn't an issue, and is pretty instant. I'm using mine virtually all the time, it seems, up here in the Highlands.

Not got a partially blocked flow, or it is draining back to the front tank?

HighlandPete

[DaveB]

Thanks Pete.
I'll maybe take it to bits at the weekend to have a good look at it.
Let me know what yours does so I know what it should do?
Thanks again.

[Tom K.]

Just checked my '07 E91 and the washer starts immediately, so that by the time the wiper has gone through about 1/4 of it's travel, the window is sufficiently wet.

I do notice that since one must go through the wiper ON position to get the wash, are you sure you are depressing the lever as quickly as possible? If so, then perhaps there is some blockage in the line to the rear washer.

I had the opposite problem, where the rear washer worked perfectly, but the fronts would only dribble a few drops, plus there was a puddle of fluid near my left front wheel. The problem turned out to be a washer pump strainer clogged with debris.

Good luck in sorting it out.

Tom

[DaveB]

Thanks Tom.
At least it looks like my car's not behaving as normal which is some comfort.
Looks like I'm going to be smelling of washer fluid on Saturday...