I am new to the site so bear with me please. I am having an issue with my blazer. I have a 97 Blazer with a 4.3L W motor and have intermittently gotten the codes p0131 and p0151. My scanner tells me that these are O2 low voltage codes to bank 1 and bank 2. I have recently given my blazer a full tune-up and replaced the fuel pump a few years back. Could two O2 sensors go at the same time or am I looking at a possible fuel pump issue? Pressure on the pump @ key on is good (55 psi) and running is good (53 psi). Any input would be greatly appreciated.

 

For help working through the two codes, read:

P0131 Explained

P0151 Explained

The fuel pressure reading is close to marginal. Read through:

96+ Fuel System Diagnosis

 

Thank you for the reply. I will definitely use these to my advantage. After reading through some of this though, it sounds like my fuel pump could be getting ready to give up the ghost again. I have replaced it twice now, both were delphi pumps. Will test my pump further and post back with results.