Bad 02 Sensors..No Check Engine Light??

[rude_life]

IS this possible? Can your 02 sensors be out of commission without throwing a C.E.L?? Im about to buy new ones just to be on the safe side.

 

[jermy82]

I'm pretty sure it can be bad since I've run my car momentarily with open headers and O2 sensors not even hooked up and it didn't throw a CEL at me. But like you said, it couldn't hurt to replace them if they have quite a few miles on them anyway.

 

[Car Nut]

How often should O2 sensors be replaced? Like every 30K miles or more?

I've wondered this same stuff myself. Can't completely rely on the check engine light.

 

[wytstang]

Most bad o2's won't set of the CE light.

How often should O2 sensors be replaced? Like every 30K miles or more?

Just when there bad there not cheap.

 

[HISSIN50]

but one has to run the car long enough for them to light off. as they age, they stop switching as quickly and lose their switching range. they can be pretty jacked and still not trigger a light.

 

[gcomfx.com]

I just bought new ones for my car. Old ones looked original and had 170K+ miles on them.

Basically I wasted $100.