Chevy S-10 1999 PCV replacement and Oxygen sensor replacement

JDUARTES10

MEMBER
1999 CHEVROLET S-10

I have a Chevy S10 with 165,000 miles 2.2L 4cyl. The truck drives great but it is not passing smog. I placed a new catalytic converter on it 2 years ago at 110K and it passed afterward. Now it wont pass again. I want to change the PCV and O2 sensor but can not locate them. I have a repair manual but even that does not give an accurate description of the location. When taking of the intake box to expose the valve cover we noticed there is oil in the intake box which could contribute to the poor emissions. And we thought the pcv was on the valve cover but were not sure enough, because it wasnt easy to move it, so we left in place til I could get more expert advice. I really need help and am more than willing to give a donation for the site. Please help somebody!

1 Reply

MERLIN2021

MECHANIC
17,250 POSTS

Firstly, What color is the oil in the air cleaner? With the engine running, remove the oil fillir cap and see if any blue smoke comes out. If yes it will most likley never pass smog test. 02 sensors are on the exhaust before and after the converter. All I can locate about you PCV is that it's controlled by the PCM, This means it's not vacuum operated. Is it clogged? If there is whitish oil in the air cleaner and or under the oil filler cap!