i just got the car and it looks like nobody had done any routine maintenance in quite a while. it was real slugish when i first got it, but after replacing the air filter with a kn/like setup, plugs/iridium, and ignition wires it has really livened the car up. when i was replacing the spark plug wires, i noticed a lot of corrosion on the coil tips. so now i wanna replace the coil. i am gettin a lot of codes intermittently p0101, p0139, p0174 and p0300(alreadly looked them up on the forum and got a plan. these codes may or may not be related to the coil, but i was wondering what kind of preformance upgrade, i could get if i went with a preformance coil?