Ark

i curently have done some work on my 1998 subaru impresa 2.2 i took it to the local parts store and put it on the obd reader and it was throwng p0303 code so i proceed to change wires and plug witch seems the most logical thing to do . So i removed the winsheild wiper fulid box and the battery to reach 2 and 4 cyclinders and thats it then i tried to restart the car after and now it will start but as soon as the car goes back to idle it dies and all i have done was change all four plugs and wires . and now the flshers stay on even with the keys out of the ignition so i am wondering if anyone else has this same problem or any solutions, i read some other threads on the code but no one mentioned it not starting after changing the plugs and wires, has any one heard of this? could the light thing be a battery issue, maybe i have to reset the ECU