So i recently bought a 2004 g35 coupe. It had 6 check engine codes:P0300 CNF Mod 10,P0011 CNF,P0300,P1805 PND,P0327 PND Mod10,P0327 CNF. The car sometimes made a thudding idle at idle and if misfired a ton, went into limp mode and cut power at all times when the check engine was on. Now the check engine is not showing up, i have a smooth idle and there is no power loss at all. Did the car just fix itself somehow? The rear brake-lights still don't illuminate but all the other problems are fixed it seems. I have no other symptoms of the other problems. Could it just be one wire shorting or loose causing the sensors to act all whack? Or is this going to be just a temporary thing then suddenly everything will come back again?

Was this car ever in a flood?
Flood cars are known for weird symptoms.
The vehicle is twelve going on thirteen years old and a purchase of a vehicle that old should have been checked out and the VIN number run by an Infiniti dealer. Better to spend a hundred or so at the dealer then now be stuck with large repair bills.

Good luck

Telcoman