Idle problems

I've got a 92 xj and it's not wanting to idle right or stay running for that matter. I drove it one day for about 5 mins shut it of for maybe 3 hrs and ever since it won't idle or anything. Put a new iac and tps in it and now it will start and rev to 2000 rpms and then idle down to about 500 then shoot back up and then die. If I hit the gas it will kind of bog out. I don't know what else it could be. It's not throwing a code at all. Any suggestions would help. Also just had a tune up around 1000 miles ago.

It actually is throwing codes. It's obd1 and it's flashing codes 12,23,24,25,55

I figured out those are for iac tps and intake air. It's all new besides intake air temp sensor. Still not sure. It's only 23,24,25. 12 is battery disconnected 55 is nothing.

I would suspect a faulty battery, alternator, or poor wire connections.

Battery is only 6 months old alternator is only like a week old and connections seem to be good

Just tested with different battery and did same thing. Connections are good