94 century 3.1 surging

[don7]

Just bought the car off of my friends sis for a winter beast. and it sometimes had a rough idle and stalls out at a stop. i have already found one problem, that where the spark plug wire connects to the coilpack was very rusted and the spark was coming out the bottom of the boot. so first thing is to get new wires.

is there anything else that i should check? it surges under accelleration. if i wiggle the rusted terminal around i can stop a majority of the arcing and it idles better the surging stays no matter what.

the rusted coilpack is the one farthest to the right if looking at the engine from the front of the car.