I recently purchased an ignition module harness adapter allowing me to use the 86-87' unit in my 84'. The installation is straight forward. The package included instructions asking you to use the firing sequeance stamped on the updated coil pack(86-87'). I've followed the instructions carefully. I followed the firing sequence engraved on the 86-87' coil pack and made sure the ingnition wires were not mixed when I intalled them. I even tried fastening the ing. wires the original way but I continue to have a miss at idle and backfire thru the intake upon accelaration. Could the module to coil wires(blue, yellow, etc.) have been mixed up ? Please help.