Issues after rebuilt engine install

[PJF 97 Jeep]

I have a 97 TJ 4 cylinder. I have a rebuilt engine. And recently had a bunch of issues.
New parts
Fuel pump
Distributer
All ignition parts
New O2 sensors.
Now when I start it it will back fire. Only does this speratically . Check engine light comes on and starts blinking. Then clears out then runs fine and check engine light goes off.
Anyone ever have this issue?
Super frustrating!!!

 

[Chris]

Scan it with an OBDII scanner and report back with which codes it’s throwing, both pending and stored.

 

[PJF 97 Jeep]

I am heading to a buddies on Saturday to give me a hand. Although I did disconnect my battery the other day. It it ran great after that. For about 100 miles. Then ran bad again. Last night I disconnected the battery again. Today it ran fine. I had a mechanic look at it told me I had a stuck lifter. I am not believing that. I also put a reman head with engine rebuild.
And apologize for posting in the wrong spot. Not seeing the post tab in the upper right corner of my screen

 

[astjp2]

Reman, does not equal quality parts all the time, backfire is a sign of an exhaust manifold leak. Just one of many possible solutions.

 

[PJF 97 Jeep]

Had another diagnosis. For the misfire. Of course when I showed up at my buddy’s house it was running just fine. No codes. He gave me a noide tester for the fuel injector. We pulled #1 injector off while it was running good. Immediately had a misfire and check engine light. This morning I had the misfire pulled the injector. Hooked up the noide light and was blinking. So right now I am leaning towards a bad #1 injector. Although more expensive I will be getting one from the Jeep dealer. Learning one thing with jeeps they do like Jeep parts when it comes to electronics. I will keep ya posted. Hope this takes car of the misfire