On my 2001 dodge neon se 2.0 when i try to start it it just keeps cranking but wont start the fuel pump is good its getting a spark the battery is good to it was running pretty good til it started doin what i just said and when its turning over it seems to backfires or like pops from the intake i check for codes and all im getting is P0743 would that have something to do with whats going with it not starting