WE have an 01 Camry LE, 85K miles with the 4 cyl motor. Not sure the cubic inch but there is only one 4 cyl. At 85K miles we are having the timing belt replaced. Should we have the valves adjusted (250.00) There are no noisy valves, but we understand exhaust valves can tighten. Does this engine have a history of requiring a valve adjustment at this mileage? Thanks. Wad.