Title speaks for itself.

This is the second time I've changed the same bank 1 front o2 sensor in 5 years. I also changed the o2 adapter.

The readiness DTCs are stuck at Catayst: Incomplete.

These are complete:
Misfire: Complete
Fuel System: Complete
Components: Complete
Evap Sys: Complete
O2 Sensor: Complete

Please help. I've taken it to an independent Volvo shop and they said "take it to the dealer". They said Volvo has to expand the ECM settings for acceptable O2 values.

 

What year Volvo? My 2001 has an extra wiring harness between the original connection on the firewall and the O2 sensor's wiring harness. It seems there is a factory goof with the original harness having the wires in the wrong position. The extra harness fixes this issue.

Does this apply to you? If so, did you remove the harness when you swapped sensors?

 

Yes, 2001 s40 as well.

I updated the original post with the adapter answer. Yes, I already had the original harness replaced around 10-12 years ago. I replaced it again last week after changing the O2 sensor, because I couldn't figure out the P0133 problem.

Could it be a exhaust leak? I found the possible cause here (http://www.obd-codes.com/p0133). I'm not sure how to check for that. I've been reading about it on the Matthews volvo site, but the pictures are missing from the most important post (http://www.matthewsvolvosite.com/for...hp?f=1&t=54895).

 

Assuming the O2 sensor was good out of the box, you have to start looking elsewhere. Wiring condition, low fuel pressure, intake vacuum leak, exhaust leak. Not fun. I would suggest swapping the lower O2 with the upper O2 but I don't think the connectors are the same.

 

SOLUTION: Fuel leak from the Fuel Pressure Regulator. I had to go to the dealer to find the root cause. $100. I probably didn't even need to change the O2 sensor. Why the code for the Fuel Pressure Regulator didn't go off, I'll never know...

I used this link to replace the part. It was incredibly easy. I sucked it up and just bought the replacement fuel pressure regulator from the dealer. $300. Ugh. It was $160 at NAPA.

https://volvoforums.com/forum/volvo-...t-guide-64228/

PLEASE CLOSE YOUR THREADS WHEN YOU FIND SOLUTIONS!!