Hi i bought my truck used and when i was changing the radiator i noticed the harness that normally goes to the expansion tank for the coolant level was missing. The sensor is on the expansion tank and it looks like it has been changed previously but no wire?? I have worked on a lot of M54 engines and have never seen this wire missing. its usually hanging right there! can anyone tell me if this is normal for the 2001 3.0 later version?