Hi. i'm new to this forum but i have a 2000 xterra 2wd. and i'm having the worlds worste problem with it.When i first start it up it runs fine,but after about 20-30 minutes its sputs and shakes and eventually stalls out and die.It will start right back up but the rpm just goes up and down.If i let the truck sit there for about 20-30 minutes it will run for awhile and start to do the same thing any suggestions? I've repaced the maf,crank sensor and i still keep getting obd codes 335 and 325. please help me!