I've been having some difficulty with the service engine light, brought it to Nissan and they said I have some misfiring in the engine coils and an issue with a fuel leak in the precat?? I've read up on both of these in the other postings, but didn't see any mention of the two showing up together. I'm pretty sure I'm joining the club with figuring out which is the bad ignition coil, but is it possible the problem with the coils is triggering this other error? Taking it to the local shop tomorrow, was planning on having them take a look at the coils first and see if that fixes both problems.

 

this may not help you, but i had P1320 and a P0430. My coils had already been replaced. If you haven't replaced your coils, replace them all. Nissan started unplugging connectors and reatatching them and told me it just dissapeared. They aren't sure why but it did and it hasn't come back. As for my P0430 code, it is a rear O2 sensor. I plan on getting an O2 sim eventually because i'm getting a y-pipe and I don't want to spend the money on another O2 sensor. But i don't think they should be related because the 1 code just means there is a misfiring, which shouldn't affect the sensor. Not 100% sure though.

 

P0420 usually means reprogram ECM as per Nissan Bulletin, which is covered for 8yr/80K.
P1320, in combo would mean that coils need to be replaced, cause outside parameter readings of down stream HO2s.
Get reprogram first, acknowledge you have a P1320 stored in memory, but would like to see if its 'something' else.

If 1320 comes back, you know its coils :-P