hi so i just bought an auto 2006 maxima and I replaced the timing chain guides and tensioners, as well as spark plugs and drove it back an hour and half but the car only stays running if your holding down the gas and it also will cut out and die if you put it in drive. every other gear is fine, you have to drive it on the paddle shifter. only code is for the o2 sensor (P0031: HO2S1 Heater Bank 1). any ideas?

 

I would start here.