Header-related CELs

[LEJ]

At 62000 miles I got a Check engine light telling me that the O2 sensors were "aging" Cleared the code and got it again. The code was for a specific O2 but I went ahead and bought 4 and replaced them all. No more Check Engine Light issues. You indicated that you have 86,000 miles, I suspect your 02's are also "aging"

[Frodo]

Originally Posted by LEJ

At 62000 miles I got a Check engine light telling me that the O2 sensors were "aging" Cleared the code and got it again. The code was for a specific O2 but I went ahead and bought 4 and replaced them all. No more Check Engine Light issues. You indicated that you have 86,000 miles, I suspect your 02's are also "aging"

With similar provocation I replaced just the 2 post-cat O2 sensors at 53k miles. That resolved my then-current CEL problems until (7k miles later) we installed the headers.

I hate to randomly replace all 4 of them when I'm pretty sure at least part of my problem is the headers. They're not exactly dirt cheap! Is there any way to actually check whether an O2 sensor is in good shape or not??

[itsnotanova]

Don't quote me on this, but I believe the last two O2 sensors only tell the car that the precats are/are not doing their job. The rear O2's don't actually tell the motor to change anything. The ROW flash will turn off those rear O2 sensors so they won't trigger an engine light.

[Frodo]

Originally Posted by itsnotanova

Don't quote me on this, but I believe the last two O2 sensors only tell the car that the precats are/are not doing their job. The rear O2's don't actually tell the motor to change anything. The ROW flash will turn off those rear O2 sensors so they won't trigger an engine light.

Yeah, from everything I've read that's right. Again, though, I don't have the means to reprogram it. And I suspect shops in the business of working on cars would't be willing to do so---I suspect (though don't know for a fact) that that would get into legality issues.

I'm in Ohio...anybody in this neck of the woods with a Durametric, etc, that would be able to help with this? Feel free to PM. (BTW, I confess that I'm unclear on my terminology: Durametric vs PIWIS vs PST2...the distinction between them I'm a bit unclear on )