'89 Cutlass Ciera Timing Belt/Chain Issues?

I have an '89 Cutlass Ciera SL, 2.5l, with about 175,000 miles on it that I need some help or advice with. A couple of days ago it began losing power slowly, steering became sluggish, as I was exiting the freeway. I heard a noise in the front, seemed to be on the passenger side, sounding like a belt flapping around. It wasn't very loud and didn't last long, a couple seconds at most, then changed to a whirring sound, then nothing. I managed to make it off the freeway before the engine died completely and all dash lights came on. Checked under the hood to see if the serpentine belt was gone but all looked fine. No liquids leaking from anywhere that I could see. The engine cranks when I try to start it but doesn't catch. A friend said it was probably the timing belt, which I understand can be a pain to replace, and my model may have a timing gear instead, which is even harder to replace. I haven't checked the computer diagnostic codes, yet. Any suggestions or ideas?

The 2.5L 4cyl. engine does not have a timing chain or belt. It's a gear drive which should last 2 to 3 hundred years with regular oil changes.
Do your code check.