Hi, I have 2001 Xterra se with nearly 238,000 miles that has some problems when driving. To start off, I recently inherited this car a couple of months ago and it had a cracked exhaust manifold. Once I replaced that manifold, the car ran perfectly for around a month. Recently though it has begun to sort of stutter when driving down the road. It only happens when I give it throttle and it makes the car sort of jerk or stutter like its losing power. To try and fix the problem i have replaced the spark plugs, spark plug wires, the distributor cap and rotor, the fuel filter, and very recently the TPS as well as cleaning off the MAF sensor. None of these have solved the problem though. I don't hear any sort of vacuum leak when the car is idling, and it seems to idle decently as well. I really hope someone can help me because I don't want to keep dumping money into it if its going to be something like a fuel injector. Any help is appreciated, thanks.