I believe I had a code 42 a while ago and did some tests of a few things and found after pulling the distributer cap that the pickup coils protective coating had started to disappear. I pulled the distributer and changed it and that was the end of that.
now I say always test never just replace parts at random because it can get very costly. but if you see the coating starting to disappear around the pickup coil and an intermittent check engine light when the engine starts to run like crap chances are that could be your problem.
Edit to add, it could have been code 43, my memory is shot and it was last year or the year before.
Technology is great when it works,
and one big pain in the ass when it doesn't
Detroit iron rules all the rest are just toys.
[This message has been edited by 84fiero123 (edited 11-08-2013).]