Any hints for this bumpy ride mystery?

[Starty04ion]

ISSUE: Unidentified vibration/bumpy ride

// SYMPTOMS

• Bumpy bouncy feeling in seat, seems like pass. side, changes with speed
• Possible slight whirring sound, changes with speed, sounds like something that is spinning, could be a normal sound
• NO other loud noises, clicking, squeaking, etc
• Wheel does not seem to pull in any direction

// CONDITIONS

• Experienced while coasting (most noticeable), accelerating and braking
• Most noticeable/bouncy within 20mph to 30mph
• Less noticeable at higher speeds, but still present

// PREVIOUS ACTION

• Brakes done, including rotors (no change, needed to be done anyway)
• Tires rotated and balanced (no change)
• "Bounce Test" for shocks/struts (stood in then jumped out of the trunk, seemed ok...was entertaining. Ride is not bouncy in general)
• Front and back bumper covers recently replaced

// SEEKING Advice!
Does this sound like anything familiar to you?
Anything else I can look for or do that could help me pinpoint this?
Would it have been obvious when balancing the tires if there was something wrong with one of them?
Wouldn't anything wrong in that area have been obvious when the brakes were done?
I was also rear-ended about a month ago, but neither the mechanic nor the collision place said anything looked wrong (apart from the bumper). Anything there?

Suggestions, similar experiences, commiseration, etc. welcome and appreciated.
Please help me help my Ion.

[ruley73]

I still say bad shock & struts are to blame. I've found that the common bounce test as described and preformed by most people is irrelevant. The way I do the bounce test is to suddenly push down on the front radiator support or the rear bumper/trunk area. I feel that if you are able to increase the intensity of the bouncing when you reciprocate the recoil by pushing down again, the struts/shocks are bad and need to be replaced. Shocks/struts that are good go stiff almost right way if the front or rear is suddenly forced down and will not allow you to keep bouncing the car.

This video actually demonstrates what I mean very well. I will say that the bad shocks on the vehicle in the video appear to be a pretty extreme example though.

[Belac360]

Bad suspension will cause this whirring sound you are hearing. I'm getting the same sound on my car and mine need to be replaced. If you let it go long enough your tires will start to wear in a diagonal pattern on the tread.

[Starty04ion]

Thank you for your responses!

Probably should have mentioned, my Ion has about 93,000 miles on it.

I recently got an inspection at the Dealer while they did my recall work and they listed front struts as a concern (said "worn, noisy"). I thought it was just the dealer doing the dealer upselling thing. I took it to my regular mechanic for the brake job and they didn't say anything about it. I also thought the overall ride would feel worse if it was shocks/struts; like when I go over a bump, it seems fine, not too bouncy.

I am going to bring it back to my mechanic and ask them to take a look. He originally said i had a stuck caliper or something and the brake job would fix the issue (didn't).

Driving it today with no music and the windows up helped me hear the sound better, and it is a bit like a quiet helicopter.

What do bad wheel bearings sound like on an Ion? I don't have any sounds apart from the whir.

The other items listed my the dealer were:

• Leaking right front axle seal (my guy said it was a "seep" and is ok)
• Worn front sway bar links

I didn't think those would be related to this though.

My top three contenders are now tires, wheel bearings, and struts.

[kevin.st56]

i like how you posted your information. should be a common format when it comes to troubleshooting issues lol

anyways, when you hit a large bump, is your car bouncing for the length of a city block? lol

as for the whirring noise, my thought would be wheel hubs, which have the bearings. they are pretty simple to remove.

swaybar endlinks may not be related to the issue, but still a good idea to change. moog products are pretty good.

[Starty04ion]

Originally Posted by kevin.st56

i like how you posted your information. should be a common format when it comes to troubleshooting issues lol

anyways, when you hit a large bump, is your car bouncing for the length of a city block? lol

I'm a graphic designer, so it comes by habit

The thing is the ride--even over bumps--ISN'T really bouncy, so that's why I wasn't sure about the struts thing. It's just the certain speeds (over flat roads) i get the bounce.

I didn't seem to have ALL the symptoms for any one problem (I thought wheel bearings were usually noisier than a whir).

[Starty04ion]

Sorry for the double reply, couldn't find how to edit the last one.
I'm sure I'll be back if the issue isn't resolved by this, but I HOPE it is. Really stupid that the guys at Discount Tire didn't notice anything, balanced them and sent me on my way. Over the phone the mechanic thought it sounded like wheel bearings but i guess they checked out

Belac and ruley are the current winners on this one!
In case anyone skims the thread looking for the solution...

ISSUE UPDATE
// DIAGNOSIS

• Worn struts causing flat spots on the tires
• Wheel bearings are OK

// ACTION

• New struts and four new tires
• Alignment (obviously)

[kevin.st56]

good to hear. i suggested wheel hubs, bec someone else had theirs changed bec there was whirring or humming noises coming from the wheels, and thats what gave me the thought. wheel hubs do usually last a long time on the ions, but you know how it goes. on rare occassions, things do go out prematurly.