Vibration - 986 Forum - The Community for Porsche Boxster & Cayman Owners

iamkrista · 01-18-2013, 03:57 PM

About 2 weeks ago, my back wheel came into contact with the curb as I was making a right hand turn - in a parking lot where the curb stuck out strangely. I heard a loud bang (I was driving pretty fast for being in a parking lot). I examined my 2008 Boxster and could detect no visible damage. When I drove it after that, I noticed that something felt off. The seat seems to have a slight vibration and the car feels, well, unbalanced and bumpy. The steering wheel does not vibrate though. I have driven this car every day since I got it when it was new and it was always perfect. It feels different now. I took it to a tire shop and had them look at it. They said my alignment was off ever so slightly and they claimed to have fixed it, but when I drove the car, it still felt off in just the same way. I took it to the dealership and they looked at it and they drove it and told me that my tire pressure was too high and that would make the ride seem bumpy but it was fine other than that. I know that something is off though! Like I said, I have driven this car every day for almost 5 years and I know that something is wrong! Am I crazy? The ride was never bumpy like this before. The ride used to be smooth and comfortable. It was a joy to drive. Now I dread it. If I just need the wheel rebalanced, wouldn't the tire shop have realized that? What else can be wrong? Please help!

Jager · 01-18-2013, 04:00 PM

Maybe a bent wheel... take it to a tire shop and have them look at it on a balancing machine.

thstone · 01-18-2013, 04:05 PM

My best guess is the alignment is still off or you have a bent wheel. Or both.

san rensho · 01-18-2013, 04:11 PM

Raise the rear of the car and spin the wheel to check for obvious wobble. If no visible wobble, then put a straight edge, like a wooden paint stirrer, on top of a jackstand and position it so the straight edge just touches the outer edge of the rim. Spin the wheel again and see if you can detect a wobble or out of round condition.

iamkrista · 02-02-2013, 08:46 AM

Thanks for the advice but I already took it to a tire shop and had them check for a wobble. They found nothing. I am certain that something is off though. After more driving, I notice that the bumpiness is much worse when the weather is very cold. Can this be a clue? I guess I will have to wait a litte bit until I can get my summer wheels put back on. At that point, I will at least know if it is the wheel or something else. I am sure, 100% sure, that something is wrong though. I lost the center wheel cap on the opposite side of where I hit the curb now too. That didn't happen with the original impact. But the car is so bumpy to drive now that I'm sure that's what caused the center cap to come off. Is it possible to have messed something up on the rear axle? I don't know much about cars so I usually just have to trust the dealer or the tire shop or the mechanic. If they tell me nothing is wrong when I KNOW something is wrong, I am at a loss!

jacabean · 02-02-2013, 09:08 AM

It could also be a bad wheel bearing also . in my car it was a slight vibration but not like an out of balance wheel . it keep getting more intense over time . check your axle also and your cv boots .

fatmike · 02-02-2013, 12:28 PM

Bad tire (broken steel thread)

Wheel bearing

Broken axle

Or, some combination of the above.

copsahl · 02-03-2013, 05:36 PM

+1 on wheel bearing

iamkrista · 04-13-2013, 06:45 PM

So I took it to a mechanic. He looked at the arm that holds the wheel in place. He noticed that the bolt that connects that arm had been moved on the wheel that I had hit the curb with. The movement was visible to the eye only because of the wear - the scratches and dirt that were visible due to the movement. He said that was likely the cause of the problem. But he also said that he did not have the equipment to fix that problem (and he didn't charge me anything.) I went back to the dealer and explained the issue (again) to them but also this time with the mechanic's diagnosis - and the paint he put on the bolt in question so it would be obvious where the problem lay. The dealer seemed sympathetic. But I picked it up today and while they sat me down and explained all the alignments that they had done, they didn't touch the bolt in question. And the car still drives exactly the same. Exactly as bumpy as before. At this point, I truly just want to cry. Since the dealer is insistent that the car is perfect, should I just trade it in, even though I still want the car? Should I get the exact same car but just a couple of years newer just to avoid the stress of trying to fix this? Is it possible to have an issue with a car that is just not fixable? Should I ask them to order an entirely new arm to hold the wheel? Should I just order new replacements for all the parts in question as that would still be cheaper than getting a new car? I love this car and want the car but not if it drives so bumpy. Do I have to get the exact same car, same color and everything, in a newer version just because I can't fix this one? Is this really a possible outcome?

iamkrista · 04-13-2013, 06:55 PM

Oh, and I had the winter tires changed out for the summer tires. The issue continues. So there is nothing going on with the wheels. It has to be with the car itself - or else I need to be sent to an institution. My motorcycle drives fine though. No bumpy issues. What to do? Try another dealer? Trade it in? Anyone know an honest mechanic in Chicago that could fix this? Honestly, I drove this car all the way across the country. I sat in it for nearly 10 hours a day for 6 days. Never did it feel bumpy. I have driven it a few miles every single day for five years. Every day. Never did it feel bumpy. But now, the bumpiness is obvious. I cannot live with this. Something is wrong.

thom4782 · 04-13-2013, 07:32 PM

Assuming the tire change included the rim, then my guess is the you bent something in the suspension or perhaps you toasted a shock absorber. If you used the same rim, maybe it's out of round.

fatmike · 04-14-2013, 04:05 AM

Quote:

Originally Posted by fatmike

Bad tire (broken steel thread)

Wheel bearing

Broken axle

Or, some combination of the above.

I gave you three suggestions. So far (after a few months) you've ruled out 1. I had a broken axle and bad wheel bearing with similar issues. I got mine fixed though...

If I was going to guess, I'd guess a broken axle since the wheel hit the curb. No big deal really, porsche sells them by the half (left side/right side).

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