2002 nissan maxima code p0011?

[marquand635]

My car runs and idles fine has 86000 miles problem is at about 25mph it starts to have a valve knock or so I think it does, pulled code P0011 sounds like a bunch of marbles any input would be great and some repair ideas and part locations would be great thanks to all.

[JN]

P0011....'A' Camshaft Position - Timing Over-Advanced or System Performance (Bank 1)

Hope that isn't an interference motor so you don't ruin the valves if the belt jumped a tooth or a valve problem.