Okay so I'm having a weird issue with my o2 sensors they make the check engine light come on at weird times like if I hit 93 it make it come on or if the rpms get to high to fast they will throw the code. The code says "o2 sensor low voltage" it's not just 1 it all 4 and of the rpms get to high it makes a weird "groan" sound (best way I know how to explain it) anyone else ever heard of anything like this? If I need to explain more I can!