I was getting a sporadic CEL, for active tank temperature sensor code, and asked the dealer to replace the tank under the 7 year/100k mile extended warranty. I believe walking in knowing already knowing the specific code, the integrated sensor/tank replacement issue, and emissions section of the warranty, all made a significant difference - thanks to this forum. The US $50 deductible was the least I've ever spent at a BMW dealer!

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2009 X35d Space Grey