is it time to push this piece off a cliff?

Question

2000 Avalon XLS P1135 TOYOTA - Air/Fuel Ratio Sensor Heater Circuit Response Malfunction and P1155 Sensor Heater Circuit Malfunction.
Originally I had (P0300, P0301, P0303, P0305, P1325, P0171, P0172 which are now corrected) along with the P1135 and P1155 codes which still remain.
I have changed all three O2 sensors and still getting these codes.
I have EQ 0.997on both B1S1 and B2S2 and 3.298v on both B1S1 and B2S2 Question is, is there a fusible link in the harness somewhere that could be causing the issue?
I have had to replace the fuel pump and injectors, cam position sensors and oil control valves, along with the pig tails on these parts due to Toyota mechanics stripping the wires to test the system in the past.
There are not any intake or exhaust leaks I replaced all intake gaskets when I changed the timing chain, that's when I found out the engine is a salvage engine that the previous owner had installed.
From my understanding a squirrel chewed up the wiring with the previous owner also.
Or is it time to push this piece off a cliff? Or give it and me a metal of honor for all its been through and put me through?

Answer 1

For P1135 and P1155 what usually is done is replace the A/F relay that is located in the engine fuse relay box. P1135 and P1155 is electrical problem