Neon Running ROUGH!

I have a 95 Dodge Neon two years ago I replaced the head gasket,Timing belt,Water pump and the Car has been fine until a few months ago when it started running VERY rough but only sometimes, Other times it runs fine. I ran the codes and it showed single or multiple cylinder misfire and Injector circuit error, I replaced the injectors and checked all the wiring and the harness and it stil does it sometimes, It loses power and Misses very bady but probably just 20% of the time or less. I am not losing any fluids and it is NOT running hot. Could it be the computer?? If so can I have the memory flashed into my computer or do I have buy another one??? The car is still under 100K miles.
Thanks