My 2001 Infiniti has been "knocking" lately on and off and I got a check engine light on, I did a diagnostic and 2 codes came up. P0304(Cylinder 4 Misfire Detected) and P1320(Ignition Signal Primary). I realize that the reason for cylinder 4's misfire is a bad ignition coil and am looking at replacing it my self if its possible. I do have the pdf dealers manual (fsm) but am not sure what bank or side cylinder 4 is located in. Is cylinder 4 closer to the front bumper or the rear firewall/cabin? and also, I was wondering if anyone had any input on what sort of ignition coil to put in, Im finding $33 ignition coils all over the internet, whereas napa sells them for $83..is it one of those things that really make a difference or is it like a battery or something where brand doesnt make a huge difference???
Thanks
Thanks

