I am a current owner of a nissan 350z 2004 touring model. i dont know whats wrong with it but the previouse owner did not take care of it. When im driving on the highway the tachometer is at 5000rpm then goes to 0 then back up again. the car accelerates slowly sometimes and the slip/vsd and cel throwing a bad o2 sensor with a low voltage knock sensor any help on what these things could be would be much appreciated.

 

Take it and have a proper diagnosis done on it

 

Welcome, but you didn't include any key facts about your Z. Things like how many miles are on the odo, how long you've owned it and when these "weird" symptoms began happening. Also, any mods that may be involved in the problems?

Likely, you have several problems going on at the same time. Start by taking it to a shop that specializes in Nissans, or find a trained technician to diagnose the problems locally.