How do I fix my 2000 nissan Xterra It will start up and soon as it warms up It starts missing and backfiring

It sounds like your timing skipped

time belt broke

IT IS MISS FIRING YOU ARE CORRECT AND IF YOU GO TO ADVANCE, PEPBOYS. THEY WILL FIND A CODE FOR A MISSFIRE .THEN YOU START TO HUNT IT DOWN AND THINK, WHEN WAS THE LAST TUNE UP LOW FUEL PRESSURE OR BURNED VALVE . MAKE A LIST AND START THE HUNT

Sometimes the computer will have an intermittant glitch. Wait to see if problem reoccurs and monitor it based on engine start-up/run conditions. ( I. E.) Hot, Cold, Under A Load, Idling, Cruising.

You need a distrubuter. I would not us an aftermarket one because Nissans do not like aftermarket parts for some reason. But that is most likley it.

I would start with the o2 sensor first if its not working right it will set off the knock sensor but beware of vaccum leaks sounds like your running lean

COMPUTER ISSUE.. MY 2000 EXTERRA ALSO DID THIS HAD IT IN THE SHOP FOR 2 MONTHS THEY NEVER FIXED IT SO I HAD TO TRADE IT IN AND TAKE THE LOSS! :( NOW I SEE IT DRIVING AROUND TOWN!

GOOD LUCK

I had a problem on my Nissan Xterra 2000. Symptons sound similar. In my case, it ran fine for a while and then suddenly the engine starts to stumble and lose output. At one point it did not even have enough HP to move. Irregular idling too. Thought it was water in my fuel. Bought water remover from the store and added to gas tank. Problem did not go away. Instead, "Service Engine Soon" light came on. Had to have it towed to the dealer as there was no way the engine could keep up with traffic. Dealer replaced the "Crank Position Sensor" today. Parts $33.00, Labor: $300 (about 3 hrs worth of work). Seems to work fine now but I will wait and see. Dealer also stated that Distributor bearing appears to be noisy and will need to be replaced sooner or later. I will wait for it to go before I fix that.

We are having the same problem. We are right now changing the crankshaft position sensor along with the intake and manifold gaskets.

I had the same problem and the distributor had to be replaced