Now that I've had a chance to drive the C4S in the rain I notice that the wipers vibrate a LOT on both the up and down stroke. It is like there is too much down pressure from the arm and even with a lot of rain the wiper seems to be sticking and causing the arm to make small vibrating hops.

I tried to take a video driving the car but realized that was a dumb idea. We are getting lots of rain in CO so I'll try to take another video tomorrow sitting in the driveway to post.

This does not seem right at all and is very annoying.

Anyone have any similar experiences or ideas?

Thanks!

 

Did you recently apply RainX? I had an Audi A4 once where rainx made the wipers work terribly, vibrating being one of the things that happened..

 

I haven't applied RainX, but I've only had the car a month and the dealer may have applied RainX when they detailed it. The windshield definitely seems to "shed" water even in areas where the blades don't reach.

Thinking about your post, some sort of coating causing the blades to stick is exactly how the blades look vibrating / hopping. It is not "smooth as glass"

I'll try to clean the windows with a light solvent or ammonia to see if I can remove whatever coating is on the window.

Thanks
Rob

 

The blade rubber has aged and hardened. You need to change out the blades.

 

My GTS did this from new. My SA said it would go away and it did. All of my glass sheds water as if it had a Rain-X treatment. I believe there is another product out there that is supposed to last longer which might be a bigger pain.

 

That would be my diagnosis as well. When I bought my used Turbo the windshield was treated with RainX and the wipers worked just fine. New wipers.

To the OP: Leave the glass alone and try taking a kitchen dish washing sponge the kind with the plastic pad on the back and gently wiping down the wiper blade edges. Do not use the pad on the glass!

Draw the sponge the length of the blade's working edge.

This action of wiping down the blade edges can remove some of the oxidized rubber and the blade can work better. But it won't last. But it can improve things so you can drive the car in the rain but new blades should be in your future. The sooner the better.

 

I agree with Macster.
Dried blades.

 

+1

 

I agree, get some new Wiper Blades would be the first thing I would do. Then report back and let us know if that fixed the problem.

 

Thanks all.

Have ordered a new set of blades, thanks for the link!

In the iterim I have cleaned the windshield several times with windex with amonia and used a scoring pad on the edge of the rubber on the blades.

It has finally stopped raining in Boulder (thank goodness) but more showers are forecasted this afternoon and tomorrow so we'll see if the interim steps make any difference.

Thanks!

 

New blades required. In the meantime clean the blades with some soap and water. I have also used some silicone spray to soften them temporarily.
I hate RainX. squirter juice just flies off. No time to help wash off the dirt, or salt, or bug guts.
Vibrating or chattering across the glass?

 

@Big Smoke - chattering would have been a better description.

I have ordered new blades. Cleaned the existing blades, put some griots rubber treatment on them to soften them up some and while they are a little better, I'll post after I get new blades on.

Hadn't thought that it would need new blades as it only had 18k miles, but it was a FL car and I guess the hot sun dried them out. Don't think the dealer cleaned underneath the car / car wheel wells but the car doesn't look like it has been driven in wet weather... very clean. So maybe the wipers never got used.

I'll post next week after wipers get on and close this thread.

Thanks.

 

It's never a bad idea to replace your blades or blade inserts, but your chattering can also be caused by some product on the glass.

When I recently detailed my car, I cleaned the glass meticulously and then applied Zaino sealant to it. I have done this on other cars and it acts like Rain-X, only it lasts much, much longer and doesn't give you rainbow halos as it wears off like other waxes can. Every time I've used the wipers since, they chatter on the glass. It's very annoying.

Annoying enough, in fact, that I'm going to try to get the sealant off of the glass the next time I wash the car. I'm not sure why this product works on all of my other cars but it certainly is causing problems with my 997 and since the wipers worked flawlessly just prior to the Zaino application and then chattered incessantly right afterwards, the correlation is just to strong to ignore.

 

I had the same exact issue. As others have said, you need new blades. After I put on new (OEM Porsche) blades, the wipers sweep so smooth, you'd think the windshield was covered in vaseline!

 

Like I mentioned earlier, I had exactly the same thing on a brand new Audi A4. Maybe 500 miles on the car, and the windshield wipers chattered like an old rustbucket.