ok guys i need some help with this code 1345 1997 chevy tahoe 5.7 redid the heads and injector about 2 years ago (just one injector) the service engine lite has bben on steady since now has a real rough idle and not running good at all and lite is now flashing at times had codes read at local parts place they gave me 7 codes that were in there o2 sensors random misfires and 1345 with no definition not sur what to do next also had trans rebuilt and new ecm put in about 6 months ago any thoughts?