2000 Volvos S80 misfire

[jaru]

Thanks, why is fuel sys 2 still open? Do you know what is fuel sys 1 and what is fuel sys 2?

[draser]

This is where it gets confusing. If you have a six cyl engine it may be bank two, cyls 3-6. However, I only see one O2 sensor before cat. Both of your O2 sensors seem to have very low signal, either old sensors or poor connector contact. All 3 data sets show low signal or lean condition. I'd try spaying propane or brake cleaner in intake to see if sensors switch to high, or 0.8 volts. If they don't you'll need to replace. Open fuel system 2 is caused by O2 sensor low signal and ECU thinks it's still open loop. Do you see one or two O2 sensors before cat?

[jaru]

Dreaser you have been great help! I think you're right that the o2 sensors in bank 2 are not working. I didn't physically check how may sensors there are, but I believe there are 2 in bank 1 and 2 in bank 2. I sprayed some brake cleaner in the intake like you suggested, but nothing changed in the read out. I noticed that when the rpm's get to approx 2000 rpm the fuel sys 1 and fuel sys 2 both say OPEN2.

[draser]

Follow the sensors wiring from the sensor out towards ECU and unplug every connector to make sure contacts are clean, and wiring is not damaged. I would even unplug ECU to make sure connector contacts are clean. If you don't find damage then need to replace sensors. Not sure why scanner only sees one sensor pre-cat and one post-cat.