i have a 97 sts and i have a current code of p0340 for camshaft position sensor circuit. Exactly what does this mean the car runs fine although it does seem like its loss a tad bit of power on WOT and I also here something that sounds like the valves are tapping. Does the sensor need to be replaced? and is it easy or one of those dealer only jobs. Thanks in advance 2 any1 that can help me with this.