One problem related to funny engine noise has been reported for the 2004 Toyota Matrix. The most recently reported issues are listed below.
After last oil change, oil was gel-like, engine made tapping noise. . . Took to dealer with a list of other problems, ac not cold, heater not blowing hot, window jumping when rolling down, and tires making funny noise. Was told engine noise was normal, fixed ac again, 3rd time, heater had loose part tighten, window part ordered, tire had flat spot, last time was water in wheel. Crash did not damage engine, or windows, or tires.