I just got an 2000 v6 and it started throwing a misfire on cyl 6. So we changed the plugs and wires. The light went off then came back on. So I brought it to autozone and got it checked and it said misfire on cyl 1. So we changed the fuel filter and coil pack, but its still has a miss to it and it only does it between 1000-1700 rpms. Any ideas of what it could be?