Wiper overshoots, but rests properly

[Nuje]

2003 Golf. Driver side wiper works as it's supposed to.
Passenger side, though, when wipers are "off", rests relatively high (as seen in photo below), but then once it starts wiping, it slaps against the plastic cowling most of the time (very annoying during the rainy season here). Oddly enough, maybe 30% of the time it does wipe to the correct depth.

When I was fiddling with the wiring for the auto-->5sp. conversion, I pulled out the wiper assembly (it was happening before) and made sure when it went back in that the driving arms in the plenum chamber were parallel.

Any ideas on how to fix so that it doesn't repeatedly wipe too "deep" and slap into that plastic cowling?

 

[snakeye]

Have you disconnected the motor from the linkage prior to this happening?

 

[Nuje]

I don't recall separating the motor from the linkage; I'd just unplugged it, took everything out, seemed solid, put it back in, aligned upper / lower arms to be parallel to each other. Same symptoms as before.

 

[Tdijarhead]

Those wiper studs are knurled, is it possible the the passenger side is stripped or partially stripped?

 

[Nero Morg]

Having the linkage even a little out of adjustment causes them to be all over the place. I'd inspect to see if any of the linkage is loose.

 

[Nuje]

Those wiper studs are knurled, is it possible the the passenger side is stripped or partially stripped?

Not really; I looked at the post, and even put a different wiper arm on there. And it's never "all over"; it just rests like you see there, but then most of the time it's wiping, it overshoots that position on the downswing.

 

[Nuje]

Having the linkage even a little out of adjustment causes them to be all over the place. I'd inspect to see if any of the linkage is loose.

I do have access to another linkage; may be time to give that a try.

 

[snakeye]

Those wiper studs are knurled, is it possible the the passenger side is stripped or partially stripped?

That's a good guess. The wiper arm could be flopping around. It's usually the arm itself that corrodes and strips, though. I doubt it's the linkage itself.

 

[Nero Morg]

I had the nut for the motor fall off on me once, conveniently when it was absolutely pouring on my way to work. Thank you Oregon weather.

If you don't have it aligned just right, they'll come to the stop position just fine, but may interfere or go further than the windshield. I had to adjust mine four times to get it just right. Blue locktite and it hasn't been an issue since.

 

[Tdijarhead]

Two years ago we had a heavy wet snow fall and I had to drive in it. Not only was it snowing like crazy it was piled up deep enough in the road to blow over my hood. The bottom line was that the heavy snow bent the linkage that runs the blades as they tried to keep my windshield clear. I only had about half a sweep from both wipers. I pulled the linkage and straightened everything back out and it’s been fine ever since.

 

[Nuje]

That's a good guess. The wiper arm could be flopping around. It's usually the arm itself that corrodes and strips, though. I doubt it's the linkage itself.

Indeed - the post seems to be steel, while the mounting hole of the wiper arm appears to be aluminum. So, the post will "cut" slots in the aluminum arm to make itself fit. In my case, when the nut is tightened down, the arm is affixed solidly; there's no ability to move it up / down / around.

 

[MillionMileClub]

03 Golf here. Mine truly have a mind of their own. Won't respond to any speed setting. Stop mid-swing. Start at random intervals. Wondering if anyone else has experienced this and has a starting place to look.

 

[Nuje]

That one sounds more like a failing motor or electrical issue. Possibly the switch on the stalk (?). I'd try replacing that and see what that gets you.

 

[Rob Mayercik]

03 Golf here. Mine truly have a mind of their own. Won't respond to any speed setting. Stop mid-swing. Start at random intervals. Wondering if anyone else has experienced this and has a starting place to look.

Sounds more like the pivots in the linkages siezing up - I replaced my whole linkage assembly a year or two back because they stated not working, or stopping mid-swipe. When I got my original linkage out, I found the driver's pivot completely siezed - I still can't figure out how the plastic gears in the wiper gearcase didn't totally blow apart turning it, because I couldn't budge the thing by hand with a cheater bar.

IDParts has the linkage for $59 right now, and it's maybe an hour's job at most to change if you're really taking your time.

 

[KrashDH]

That one sounds more like a failing motor or electrical issue. Possibly the switch on the stalk (?). I'd try replacing that and see what that gets you.

This. Intermittant wiper issues on the timed settings usually trace back to the actual wiper motor connections deteriorating internal to the unit. The ground contact is usually the one because for timed wipers the circuit is constantly opening and closing, it wears out just like starter contacts, then it goes crazy. It's happened on my car and truck.

 

[Bob S.]

My thinking is along the lines of the b2 preceeding Posts. From my experience with , I would try cleaning the grounds + connections. If for no other reasons to eliminate them as a problem source. I would not have believed the issues a high resistance ground caused in my wiper system.

 

[Nuje]

Turns out it was much simpler than wiring / electrical gremlins (kinda sorta): The centre pivot post to which the passenger-side wiper control arm attaches has a rubber grommet, which on my car's wipers, was very worn, resulting in the wiper linkage arm having a bunch of play, so sometimes it over-wiped and other times, it didn't, and rested as shown in my initial photo.

Here's a couple photos of the problem part involved; replacement part number for the rubber grommet is 701955754 - approx.$3.
Edit: That part number quoted above....not correct. Seems like the grommet in the photos below are plastic and molded into the wiper linkage arms themselves. Grommet goes with the metal bushings through which you drive the three bolts to attach to car - you can see one in the bottom right of the second photo.)
So - looks like solution is replacing the linkage arm itself (part no. 1J0955325A - approx.$10).