Yes I changed the timing belt along with the water pump and front oil seal at 110k miles. Right after I bought the xterra. Was running fine til I ran 3 tanks of gas from Circle K in it. Then the problem started. Chevron from now on. Got good spark and fuel pressure, and compression. going to swap the fuel injector on # 2 with # 1 and see if I get the misfire on the # 1 cylinder.