Just an FYI. I replaced both O2 sensors on my turbo 1995. The error codes went away, EXCEPT when my daughter used it to commute to work. Everyday, my daughter would come home with the CEL on and I would clear it. I finally asked her if the CEL came on the same place each commute. Yep, in stop and go traffic at idle speed. The code was for a failing CAT, which I recreated while on a long trip around the neighborhood.

I let the car run between 5-10mph for a few minutes and the CEL came on. I attribute that error to be the diagnostics in the computer, not in anything that is repairable. A 1,000 mile trip will not trigger the code, but I cannot drive at idle speed in 1st or 2nd gear.

As for finding a mechanic/shop that can diagnose your error code, lots of luck. The dealers have no one that remembers what an 850 looks like, much less how to use the A&B code boxes in the engine compartment. A computer cannot be plugged into the car, if your car doesn't have a port next to the cigar lighter. If there is a port under the coin tray, a Volvo scan tool can be used to watch the O2 sensor operate.


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Keeping it running is better than buying new