started to loose power gave it more gas was fine?

My son bought a 96 nissan maxima ran for an hr started to loose power he gave it more gas was fine then died he replace both crank sensors knock sensor cam sensor and fuel pump car cranks fast with spark and compression has fuel but cranks to fast timing chains are tight not broken he is driving me nuts with it tried every thing could thing of but the computer checked for power at front crank sensor while he tried to crank it no power there on both wires can you help with it might be ?

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