Okay soo when I bought my cooper I knew that the run flats would be my first replacement but I didnt think I would need to after just 1000miles. Ok check it out, I was cruising on the highway between 80 and 100 when the rear driver side tire starts to feel sluggish soo i back off. The low pressure light comes on. I duck out to a station and check my pressures. Sure enough my rear driver side was down to 20psi. I topped them all back off at 38 psi and headed back out. The tire seems to hold air below 50 or 60 mph but start to lose it at speeds above that. When I am just putting around the city everything is fine. But when I hit the highways I start to lose pressure in that tire, indicator light goes crazy.

This morning I pulled the tire off and did the soapy water test. I couldn't find any leaks. I replaced the valve stem just incase. Has anyone had a similar experience? I have read a little bit on this board about the run flats not holding air well. I even read about a guy who had to add air once a week.
Please let me know anything that can help me diagnose this problem. Any help would be greatly appreciated. Thank guys

 

Yes. One of my tires I had to be remounted. Seems I my tire developed a leak where the tire meets the rim of the wheel (called the bead).

In a more serious situation, the thick sidewall started separating from the tread at about 25,000 miles, with lots of tread left. So I replaced all my tires with regular non-runflat tires and added a compressor and can of goop to the storage cubby in the boot. However, I think the runflat system prevented a serious blow-out that might have caused me to lose control of the car, even though I think the sidewall separation was due to the runflat design.

 

Thanks Beken. Soo I guess I should just remount the tire to play it on the safe side?

 

Renn,

I'm no tire expert here, but you might have a bent rim. Sounds like your car is pretty new and a trip back to your dealership might be in order. Only so many places on a wheel to lose air and if you don't get any bubbles, you might also have a nail or something in the tire itself.

Maybe someone will chime in with better info.

 

Alright I took it to the dealer and they dunked the tire and spun the wheel and couldnt find anything. The problem went away too which is soo wierd. My guess is that Pirellis suck at holding air and the sensors and stupid me didnt notice it until 90mph. Thanks for all of the help guys and I'll keep you posted if anything comes up