so hello my name its Bryan and I own a 2003 350z, last year I had an issue that when the car was in idle, the car would start making a nocking and popping sound and the oil pressure would go all the way to the top. so I took it to the mechanic and he end up telling me that It was the oil pump and the timing chain needed to be replace. so I end up taking it to him this year and he end up changing the oil pump and the timing and after all. the car kept making the same nocking and popping sound. so he told me that it was better to change the engine, so I agree to change it , he end up putting an engine with 77k and after he replace it the car came with the situation of doing the same problems it was doing with the old engine.. has anyone had the same issue or solution to this situation?