hey guys just looking for your opinions on this one here is my novel from the beginning.. I have a 2000 xterra xe, 3.3, manual, 4x4. once upon a time i was driving (right after i bought the truck) and the timing belt broke because i never thought to ask the previous owner if it had been replaced. yes it bent valves so i rebuilt the heads and it ran great afterwards until one day i went to my local o'reillys to pick up a batt. and alt. for my other car i went in the store picked up my parts got in my truck it started ran like total crap and died.. it would not restart, i had it towed home where it sat in the street, a few hours later i went out and it started right up drove like normal into the driveway where i shut it off and it never ran again... now instead of explaining my reasoning as to why i replaced the parts i did i will just give the list yes im aware ive gone about this the wrong way but in the end i still have this "pre-existing" issue after all parts have been replaced.

NEW PARTS - fuel pump , fuel filter , fuel injectors , fuel pressure regulator , throttle position sensor , mass air flow sensor , distributor , cap/wires , plugs , 02 sensors x4 , knock sensor , several solenoids "cant remember proper names fuel related" , exhaust manifolds "had cracks" , and last but not least reman long block from rock auto. i am sure there is more i will add them if they come to me.

Now what has me all f'd up here is even with the new engine and like every new sensor imaginable this thing is still running the same way it did before i replaced the engine almost as if it was out of time but its not i have checked repeatedly you have to crank on it for about 30-40 seconds before it starts like the fuel is taking forever to get to the engine once it does start it idles pretty nice with the exception of a small but noticeable misfire and if you slowly give it throttle it will run the rpm's up but as soon as you just hit WOT it immediately falls on its face bogging "almost growling at you" until it eventually makes a stupid loud backfire out the intake i also get a lean code that tends to bounce from bank one and two.

at this point i am thinking my brand new fuel pump could be faulty? intake not holding vacuum? or computer related? i am about to go put the intake back on for the hundredth time this week and once i do that i will check vac and fuel pressure im so in the hole with this truck at this point i am willing to try anything just want to get it running so i can get my lift and wheels and tires on and tear it up haha.. again sorry about the novel thanks for reading and any suggestions are appreciated!!!