O2 sensors 1995 cougar

[billyboomerang]

engine is the 4.6 V8 and I'm changing O2 sensors because OBD II at autozone says their all bad. If I am correct, their are 4 O2 sensors, 1 before each cat. converter and 1 after each cat. converter. I only have money for 2 sensors. Which do I replace first? Thanks.

[vtwindave]

i would try more trouble shooting. possible all are bad but doubtfull they all went bad at once. look to see if something else is wrong (broken vaccum line etc...) that may cause o2 sensors to fault. try pulling o2 sensors and clean them on a wire wheel and put them back in. don't forget antiseeze.

[mikecox1]

Originally Posted by billyboomerang

engine is the 4.6 V8 and I'm changing O2 sensors because OBD II at autozone says their all bad. If I am correct, their are 4 O2 sensors, 1 before each cat. converter and 1 after each cat. converter. I only have money for 2 sensors. Which do I replace first? Thanks.

how long was the check engine light on? they could be all bad it is hard to say, bank 1 & bank 2 read as- bank 1 sensor 1 & 2 + bank 2 sensor 1 & 2 each bank reads togather you might be better off finding the money to change them all. e-mail me at [email protected] for more q&a