Don't worry- they'll replace it. I had a 98 Z3 1.9 BMW replaced mine seven times, finally after months of fighting BMW took my vehicle back and subsidized a new lease on a 2000 Z3. This fuel sending unit problem is ridiculous and BMW is well aware of it. Almost everyone on this board has had it replaced at least twice. It happens to almost all Z3's. The fact that your car is out of warranty does not excuse their responsibility to you. The problem first began while your car was in warranty. The part they replaced your initial sending unit with has the same defect. BMW has yet to design a suitable replacement part (according to BMWNA reps). Therefore, technically, BMW is not fixing your problem but providing a temporary cure until they can provide a proper fix. Whenever I've gone to BMW with a complaint which originally arose while the car was in warranty they have done the repair free of charge. My understanding from the reps I spoke to was that BMW will continue to make warranty repairs on this problem provided the problem first occured while your car was in warranty. If your dealership gives you a problem go directly to a BMW rep- and do not give up. E-mail me if you need further information or assistance with this matter. I've dealt with BMW extensively regarding this problem. It completely ruined my ownership experience with my prior z3- it used to break every six thousand miles!