did you check the drive belts? (alt and the PS)
Actually, my mechanic and Toyota said that it wasn't necessary to replace that gasket but I thought otherwise...One minor item to check is the perimeter gasket around the edges of the upper and lower timing belt covers...On my Gen 4, the upper gasket was torn and not reusable...it has 2 pieces to it...lower cover has one piece...Get the gasket from the dealer...tried form-a- gasket ...but did not work.
The benefit of having an intact TB cover gasket is that it helps to keep the engine heat/air from hitting the timing belt...and causing premature aging.