Help!! 93' YJ running horrible and stalls!!

[samm95]

Ok, a few months ago my heater core started leaking intermittenly. Seeing I haven't been driving it regulary, I didn't change it out immediately, and when I would drive it I would make sure there was coolant in the system. Last week I had to drive it a couple of days and after driving about 5 miles and stopping for gas on my way to work, I noticed steam coming from my radiator. I checked it out and discovered my radiator was leaking around the top. I waited for it to cool, opened the cap and saw there was still coolant in the radiator and overflow. I topped it off and drove the 5 miles back home.... very slowly and easy! The same night, after checking fluids again, I started it up and drove it to reposition it in my driveway, to work on it... no problem, started and ran fine! That night I changed the radiator and heater core, filled it back up and tryed to start it. It starts up, perfect for about 3 seconds then immediately " boggs down" runs very rough and almost stalls out, but I always cut it off before it stalls. The check engine light also comes on right before it almost stalls. I'm going to check the codes tonight , but I can not for the life of me understand what I did to cause this by changing the radiator and heater core??? I realize it might be a blown head gasket, but why did it run ok when I repositioned it in the driveway??

Any thoughts would be greatly appreciated!!!

[Brad The Best]

pull the spark plugs they will be clean if you have a head gasket leak , the exhaust will also smell sweet .

[Sykopro]

Did you figure out what caused this problem seeing as I am now having a very similiar problem?
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'92 YJ 4.0 and AX15 coupled to the NP231, 5" BDS Lift, Pro Comp Steering Stabilizer, Pro Comp A/T tires on Pro Comp Rims, SYE W/Tom Woods Custom Drive Shaft.