Filters are generally replaced on an as needed basis. Rule of thumb with the PCV valve is, if it rattles, it's good, just need to make sure it has good, strong manifold vacuum to it at idle. Upstream oxygen sensors are typically good for 100K miles. More than that, they can COST you money in fuel mileage. AC Delco and Denso oxygen sensor response times are the fastest, (which is good). Denso is slightly faster than AC Delco and less expensive. AC Delco lasts a little longer....it's a toss up.

 

Got all the parts ordered. They are supposed to arrive Saturday.

 

Did the plugs and wires on Monday. Man that driver's middle (#3?) was a PITA.

But it's running WAAAAY better now. Pretty sure that plug was the factory original.

It was a Delco...all the others were Auto LItes

 

I find it easier to simply disconnect the steering shaft from the box (one bolt)and move it for access to #3. Then you are not so likely to break the plug porcelain when putting it in.