89 o2 sensor w/red deposits?

[my2monkeys]

This has about 100,000mi. on it, passes smog no problem.

I just removed it to check it out and it looks like this, normal deposits for CA fuels?

 

[Ecomike]

Yes, but maybe too much fuel injector cleaner? If it was running rich it would be black. Dig up a spark plug color chart online if you want an idea.

 

[Ecomike]

Actually, the outside white part is part of the sensor surface, and the sensor measures the concentration difference between the inside and outside. That outside white part is porous.