Here's a New One...

[CJFusco]

Pulling into my driveway today in the Cayman S, I heard a weird metallic "pinging" sound coming from the front passenger side of the car; it sounded a little like two metal coat-hangers clacking together.

A visual inspection showed no problems. Since the sound coincided with the car moving, I decided to jack up the passenger side and rotate the tires by hand to see if I could replicate the sound.

Sure enough, I got it on the first try: turns out that there's something INSIDE THE TIRE rattling around in there. I'm guessing that when I'm driving at speed, the centrifugal force is enough to keep the little bugger pinned to the outside wall of the tire, but at low speeds it's just bouncing around against the tire and the rim.

Who knows what it is or how it got in there; my guess is that it's one of the TPMS sensors that came loose (I deactivated the system long ago), but I suppose it could be a wheel weight? If there are internal weights in these rims, the recent increase in heat or humidity might have caused the adhesive to come loose, I suppose.

Has this ever happened to any of you? Needless to say, I'm swinging by the local tire place to have them remove this object (and re-balance the wheel, if need be) tomorrow.

[Steve Carlton]

If it's a tracking device, just send it back to me.

[Shaun @ Tru6]

Are you missing any gerbils or smallish guinea pigs?

[rusnak]

Could be part of a valve stem or even a small nail.

[mikester]

how did you disable the TPMS system?

[masraum]

Originally Posted by mikester

how did you disable the TPMS system?

I actually like the TPMS system. It seems to be fairly accurate. But I'm a little curious too.

[CJFusco]

At the local Porsche shop, they noticed that one of my tire pressure lights was on even though the tire pressure itself was fine. They gave me the option of replacing all four TPMS sensors (since there's really no way to figure out which sensor failed), or simply disabling the system through the on-board computer, with the caveat that if I ever sold the car I should re-boot the TPMS system and replace the sensors. I guess you can do all sorts of personalized reprogramming through the on-board computer; apparently the original owner of my car also had the seatbelt warning buzzer deactivated.

[968rz]

TPS sensor broke

[bkreigsr]

Why would there be weights inside the rim? That would mean the rim was balanced without the tire on it???
If you've ever shot one of those fix-a-flat cans into the tire, it forms a big mass of green goop that eventually works itself loose.

[jhynesrockmtn]

Sounds like a sensor or piece of one, probably the one that failed. I was under the impression that the dealer and tire stores were not allowed to alter or disable the TPMS system. Interesting.

[CJFusco]

It wasn't the dealer who disabled my TPMS system, it was a private Porsche/BMW shop that does a lot of personalization/performance mods.

Sure enough, the sensor cracked in half somehow and was bouncing around in there. $20 and a half hour of my time for piece of mind? I'll take it.

[TimT]

since there's really no way to figure out which sensor failed)

Not true...

We have a reader which you hold near the valve stem on each wheel, and it will tell you the battery state of the sensor, along with other info.... i.e. sensor ID, tire pressure..

So you can identify which sensor has, or is failing... TPMS sensors seem to last 5-7 years... they just have a tiny Lipo battery in them.....

I think the reader we have can tell the s/n or unique id of the sensor....

[aigel]

Doesn't it tell you pressure in each tire? New cars mostly do now. I like it. Tires are very important - I'd like to know about a leak / low pressure condition before it goes flap flap flap.

G

[osidak]

Had this argument with discount tire last time I got tires. They wanted to charge me almost $200 to change the sensors using the claim that it was a federal requirement....... My model year VW used the sensors in the wheels but also was the first year you could tell the system to use the abs sensors for the same thing..... The tpms sensors where a known issue for false alerts so I switched to abs sensors as soon as I got the car.

[CJFusco]

I'm pretty sure it's not a federal requirement. There are cars made today without the TPS system, right? Or am I totally mistaken?

In any case, I check my tire pressure frequently, just ask check my oil level frequently. I prefer the hands-on approach, and in my experience, TPS systems are more trouble than they're worth.

[aigel]

Originally Posted by CJFusco

I'm pretty sure it's not a federal requirement. There are cars made today without the TPS system, right? Or am I totally mistaken?

It is the law since 2008!

http://www.nhtsa.gov/cars/rules/rulings/tpmsfinalrule.6/tpmsfinalrule.6.html

G

[aigel]

and of course, the vehicle comes equipped with TPS from the factory. That does not mean you are required to keep them functional. Just like you can remove or change other safety devices, like your air bag.

G

[jhynesrockmtn]

I had the TPMS go out on my Acura after about 7-8 years, sensors fail or the batteries die. I've yet to have the tire store require I fix them. They have left them alone if I chose not to replace them. What kills me is it should be a cheap replaceable battery but no, you need to buy a new sensor or 4.

[scottmandue]

I was leaving the auto parts store and ran over something... followed by the dreaded hissing sound.

I was near the tire shop so headed directly to them. I had one of those 12 volt air pumps in the car and had to stop once or twice to pump up the tire... I had the tire replacement warranty so they put on a new tire for free.

The tire tech approached me after installing the new tire.
"Your not going to believe this"
"What?"
"I found this in your tire"
He handed me a worn out disk brake pad.

[CJFusco]

Originally Posted by scottmandue

He handed me a worn out disk brake pad.

WHOA! This brings up so many questions! How is that even possible? Was it wedged in there? Did they somehow balance the wheel correctly even with the detritus inside the tire?