A friend of mine just bought a 2001 Accord EX V6. It ran great until he had an ignition key made at Wal-Mart and tried to start it, the car wouldn't start the car, so he used the factory key which of course started it (I think it has a code chip in it). Now the car has a misfire in cylinder #1 according to the DTC P0301. Could using the non factory key have caused this, or is this just a coincidence? Does anyone know how to fix this problem if it is indeed caused from using the wrong type key?

Thanks,
Mike

 

I think it's just a coincidence. The key without the immobilizer would have disabled the fuel & spark so it shouldn't have stored any errors from that. As far as the ECU is concerned, it was never started.