silerado classic 4.3 keeps throwing code for fuel injector and misfire, plugs, wires, injectors and coils have replaced

What is your question?

looses power when going up hills, trans slip hard from 1st to 2nd. Has 214,000 mlies on engine

What makes this problem better or worse?

worse when on a incline

How long has your 2007 Chevrolet Silverado 1500 Classic had this problem?

2 months