My 06 Nissan Xterra is currently overheating. I changed the thermostat did oil change and coolant flush. I did a head gasket test and the liquid remain blue with no change in color. While sitting at idol the needle spikes up gradually. I also connected my obd 2 machine and the oxygen sensor popped. I would greatly appreciate if someone can point me in the right direction to get this fix so I can start my adventure rig build.