So frustrating! About a year ago I took my 2007 BMW 330i touring in for MOT and found that both rear wheels had cracked. Got them both welded and put back on. 6 months later one of them had cracked again, so replaced it with a refurbished, never repaired BMW MV3 alloy. 3 months later, take it in for MOT again today and find that not only has the previously repaired wheel cracked, but the new one has cracked again! Now I'm looking at having to spend £400 each for some new wheels from BMW, or £200 for refurbished ones which might do the same again Not a happy bunny!
Stop putting BMW wheels back on? Complain to BMW as that doesn't seem right? Stop driving a warp speed over potholes and small children?
Well unless I want to replace the fronts as well and have a car with aftermarket alloys which will make it difficult to sell then I have no choice. And I live in the countryside so potholes are unavoidable.
This is an incredibly well known issue and was a major thing on watchdog about 5 years ago. The reality is that on a 9 year old car BMW will not be interested. Avoid 19 inch wheels and runflats seems to be the right approach. With the extra sidewall compliance of a non rft the MV3 should be ok but they are cheap on eBay now anyway.
So far only one of my MV3s has cracked and this was prior to me owning it. The style 225 and 313 are horrendous for it. I run funflats on mine and just avoid potholes. I'll be ditching them when they need replacing though.
Tyre pressure monitoring is done via the wheel speed sensor. So if a wheel is letting out air it will not be rotating at the same speed as the others and the TPM system will flag it up as such.
The only thing I was told was BMW recovery will not come out if it was for a puncture. I carried a can of foam and compressor around in the boot.
There are two systems, most BMW's with flat tyre monitoring simply do that - monitor for a flat tyre. They do this in conjunction with the wheel speed sensors and as a result do not give you tyre pressure information - simply an indication that the pressures are either 'ok' or 'not ok' in each wheel. Some BMW's do have the more complex system that gives you an actual pressure reading but it's often an expensive option. When fitted, this system uses special valves, but his E90 3 Series will be fitted with the simpler system. Stick to Toyota's (Come on, I couldn't resist that )