I recently replaced my PCV system on my 96 850T. Before that, My check engine light was on and the turbo wasn't boosting like it should. After I finished with the new PCV, the turbo was boosting and the check engine light went off; everything was great.

6 months later, last week, the turbo stopped boosting again and the check engine light came back on. I took it to the auto parts store to read the code. It showed "slow response from rear O2 sensor." The engine lacks power and has a pulsating feel when accelerating. When I shut the car off it smells of unburned gas. Could this be a result of the PCV clogged again or a failing O2 sensor.

I apologize if this is a repost. Any help or links to other treads would be appreciated. Thank you.

 

I would check the O2 sensor. I have seen them cause the prolems you have.

 

+1 If you replacethe O2 sensor, use a Volvo OEM sensor. Aftermarket ones have caused more problems then they solve!

 

Would the Bosch sensor fall into the OEM category? I tried looking for Genuine Volvo online and didn't find anything. The nearest volvo dealership is quite a drive and would hate to go out there and buythe sameBosch sensor for 3 times as much as I could get it online.

 

Bosch is OEM just make sure it is a direct fit and not a splice (universal)one.

 

http://www.fcpgroton.com/product-exe...ategory_id/170

This one? I buy most of my parts from these guys and like the way they handle their customers. Fast shipping and low prices.

 

Yes that one.