2004 Toyota Corolla Should the timing belt be replaced?

If there is noise comming from the timing belt area, it could be something else, like the tensioner, definitely check it out and replace the belt in the process because it should be changed around 60,000 miles anyway, precausions precausions, it can cause greater problems if something does cause the belt to come off, YOu will do serious valve train damage. Which will then cost alot of cash and we definitely want to avoid that

To add to excellent advice by legitimate007:

If U.S. Built it has a chain, not a belt. You can tell if U.S. Built by a sticker on inside of drivers side door jam that says "NUMMI", or look at where chain is, if enclosed in an aluminum cover, it is chain, if enclosed in plastic cover, then belt.

While chain can be changed, there is no service interval.

The noise is possibly the chain, but could also be a VVTi solenoid, or excessive shim clearence, or low oil pressure.

Start by removing coils, cam cover and measure shim clearence (engine should be cold). If shims are OK, then I would take to Toyota or trused garage and have VVTi solenoids tested and inspect chain.