If your Subaru WRX or Impreza has begun to misfire, idle erratically, or hesitate under acceleration a bad coil pack could be to blame. By providing the proper spark to the spark plug all of these running issues can be resolved. This AA Ignition Coil Pack is a direct replacement for the factory Subaru coil. Made by an original equipment supplier (OEM) these coil packs surpass the factory quality and will get your Impreza or WRX running how it should be; smooth and fast.