Intermittent, Varying-intensity vibration in my '07 Si Sedan

[ABQSI]

Well, I've scoured the forums and I think I may actually have an issue nobody has posted here before (I know folks have had vibration issues, but none exactly like this).

Let me begin by saying that my wheels, tires, and suspension are all stock. The only modifications I have made have nothing to do with those systems. I doubt my Injen CAI or Hondata gasket would cause this issue. Many of you out there know more than I do, though, so if I'm wrong, please tell me.

Anyway, about six weeks ago I began to notice a slight vibration in my car when traveling at highway speeds. This vibration is very indecisive about where or how strong it wants to be, and I can find no correlation between speed and intensity. Sometimes the car moves along smooth as silk. At other times, over the same stretch of pavement, and at the same speed, the car will be going along smoothly, then will shake a little, then smooth back out. Or, it will start shaking quite badly and then smooth out. Sometimes the whole cabin vibrates but the steering wheel does not. Sometimes, everything, including the steering wheel, shakes. This occurs at varying speeds, but is most common between 70 and 80 mph. Please don't give me crap for going that fast... I'm a good driver and willing to take responsibility for it. Besides, if you had ever lived in Germany like I have, you'd find the speed limits over here ridiculous too.

Back to the point. I took the car in to the dealer last week, and they found that all four tires were "really out of balance." Those were their words. None of the wheels had thrown weights, and the dealer couldn't explain how the tires could be so out of balance. Of course, they balanced them under warranty, since the car had only 4500 miles on it at the time. Unfortunately, the vibration has not gone away, so I've set up another appointment with my dealer for next week.

Does anyone have any experience with an issue like this? I ran across this little article written by Edmunds.com's editor in chief Karl Brauer which sounds exactly like the issue I'm having:

http://blogs.edmunds.com/karl/393

However, it's hard for me to believe this vibration is inherent in the design of the car. Wouldn't you agree?

I've had one other car that behaved this way... my 1991 BMW that I owned while I was in Germany. The problem finally went away after I replaced both front strut cartridges. I find it hard to believe that I could have one or more bad struts with such a new car, yet after reading about the problems some people have had with bad struts on the Ridgeline, it doesn't seem so far-fetched.

Here are the possibilities that are floating around in my mind:

*Water in one or more tires*
*One or more bad tires (manufacturer flaw, broken steel belt, etc.)*
*One or more defective struts*

I'm going to make sure they check all three of these areas when I take the car in for service next week. If any of you have any other ideas of things I should ask them to look at, please feel free to say so.

Let me take this opportunity also to thank every member of this 8thcivic community. This site is such a wonderful resource, and it's because of the members who take the time to post their experiences with their cars that this site can be such a God-send to people like me.

[volvo9]

Sounds like you have a tire that's out of balance slightly. My gar has almost 9k on it and it's starting to do that a little bit around 80. It's minimal so I'm not going to take it in yet. These tires are wearing pretty fast.

If it's a vibration that fades in, peaks, and then fades out in a cycle only at higher speeds then it should be an out of balance tire.

You may have to bent your facts a bit to get the dealer to fix it. The tech's are not allowed to drive 80 and will not be able to diplicate the problem.

[ABQSI]

Yep, unbalanced tire was my first thought, too. However, I just had the car in for tire balancing last week. Maybe I'll take the tech for a ride, though I'm hoping he'll be able to find the problem without having to drive the car ... a long shot, I know.
You said your car just started doing this at 9k... mine started at a little over 3k. You're right about the tires, though. They do wear fast. Maybe I'll just go get some high-performance ones put on if Honda can't find the problem next week.

[volvo9]

Originally Posted by ABQSI

Yep, unbalanced tire was my first thought, too. However, I just had the car in for tire balancing last week. Maybe I'll take the tech for a ride, though I'm hoping he'll be able to find the problem without having to drive the car ... a long shot, I know.
You said your car just started doing this at 9k... mine started at a little over 3k. You're right about the tires, though. They do wear fast. Maybe I'll just go get some high-performance ones put on if Honda can't find the problem next week.

I don't want to rule out anything other than a balanced tire, but I've ALWAYS had bad luck getting tires balanced properly at high speeds.

The best tires I've had where the ones that where factory on my new Ford in 05, they where silk smooth up till speed limiter (112). I got new tires mounted and balanced on spare wheels for winter and they where vibrating at 70. Had them redone and they vibrated at 80.

My Si has always had a slight vibration at high speeds, but now that the tires are wearing it's becoming more pronounced, it's not bad though, it's still very light.

Oh and when I worked at Acura we had a customers car (06 MDX) that she bought new and it vibrated since day one, we did all sorts of stuff to try and fix it including swapping the wheels and tires off of another car, so we ended up buying it back I think.

[galaxycivic]

Did you get the problem worked out?

[xxhaimbondxx]

This thread is old, but I'm starting to have similar problems. I have around 15-16K miles on it, all stock. Never did anything to the car other than 2 oil changes. This weekend I took it for a long trip and vibration starts at 70 mph and gets really intense at 80 mph. The whole car shakes and the steering wheel gets uncomfortable. I'm afraid to even try 90. I inflated the tires couple of weeks ago. Would rotation help of I would need to do the whole 9?

[stealth]

I'd say check the balancing and wheel pressure. I used to encounter something quite similar to what was described here and it ended up being a misbalanced wheel. I also get a similar feeling when i have snow stuck on the winter beating hubs!