I have a 1996 F150 with a 300 I6 EFI. Recently my check engine light came on. My hand held code reader gave me three different fault codes that follow:
P0155, P0141, and P0420.

I think the P0155 and P0141 are O2 sensor faults for two different O2 sensors, but I don't know which ones or where exactly their located.

Can anyone tell me exactly what these codes mean and any possible means to fix them.


Thanks for the help

 

You're right - 141 and 155 are O2 sensor circuit failure (wiring issues?)

420 is the bank 1 catalytic converter - efficiency below threshold (plugged up?)