About 3 months ago, I bought a 2001 V40 with only 80K miles on it. Within a couple hours, the check engine light was on. While getting an oil change, I had the garage do a cursory scan to see what the code was. Apparently it is fairly common: (Front Oxygen sensor slow to respond).
Being somewhat strapped for cash, I elected to go with a Bosch universal. I did the splicing and installation, took it to a local V-specific shop and had the computer reset. 4 hours later the check engine light was back on.
So.
I just got back from doing a another check of the codes, and it was the same. HERE"S WHERE IT GETS TRICKY. Normally the O2 sensor sends a signal which averages less than 1 volt. Mine is closer to 7 volts. Sounds like a wiring issue. The splices I did were by the book, but they are still the most likely culprit. How many volts are carried on the 2 white heater element wires? Is it 6?

If anyone has seen this sort of thing, or has a theory, please let me know. I'm getting desperate.
Thanks
-Bill

Oh yeah,
Hi nice Volvo people! This is my first post here.