1992 explorer running problem?

I have a 1992 ford explorer 4.0, 5 speed manual, 4x4. About a week ago my engine light came on but I didn't notice any performance problems.

A few days later I noticed my idle in the mornings was different. I would start it and it would high idle(like normal) for about 15 seconds and it'd drop real low and stay there… Usually it high idles for several minutes.

Then a couple more days later I noticed a performance difference. I feel I would have to give it significantly more gas to get it going. And a rich running smell.

The engine light will come on and go off while driving… Come on for 2 mins off for 7 mins, on for 10 minutes off for 1 min… Etc.

What could this be? A misfire? Also how can I check the engine light code? It's not an obd2. So I'm unsure lol. Anything is appreciated. If I missed something ask it in the comments and I'll reply.

Check the engine code.

Sounds like an Oxygen sensor gone bad.

You don't seem to be worried or in a hurry so take your time and Google how to read the codes, it is in there you just need to look. And then when you get the codes out Google them. But don't get yourself to worried or worked up about it.