HELP !!!! i am new here and am having a serious ammount of problems with my glaval sport blazer which i love very much !! codes are po170 and po174 some people say that Actually means mass air but mechanic says fuel pump !! please help !!!! paying 800 dollars to do fuel pump today

 

*Moving to a new thread instead of dragging THIS THREAD off topic*

Now, what are you working on? What is your truck doing other than throwing codes? Have you done to remedy the situation

P0170 - Fuel Trim Bank 1 <-- Kind of a generic code, you may want to check out the P0171 and P0172 codes. I'm leaning towards it being P0171 given the lean code for B2.
P0174 - Fuel Trim System Lean Bank 2

Your mechanic suggests replacing the fuel pump? Did he do a fuel pressure test to confirm that? If so, what were the specific results? You can test the fuel pressure yourself using a fuel pressure gauge and following the steps in THIS POST.

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