Something is wrong here. The P1357 code if for 04 and later bikes but it does mean an intermittent secondary front EFI ,only not for your bike.
The cause of this code on an 04 or later bike means spark plug wire or plug problems. I have seen a few times where the tip on the plug is loose where the plug wire goes on and that has set this code but on the 04 and later bikes.
Check with the dealer that told you this about this code and find out if they know what they are doing because it sure doesn't look like they do.