Anyone have luck using the #15717 or 15715 Bosch sensors and splicing them in? I've seen both numbers, not sure if both are 4 wire sensors. They run about $47 at auto store compared to $150 for OEM type.

There's only two sensors and you can get them from FCPGroton for about $115 each. Why "rig" your Volvo? Mike

I've used these guys:
http://oxygensensors.com/
for my latest replacement. Came prewired for $110. I didn't want to mess with the splicing, you need a very good connection, O2 sensors are sensitive to resistance (thats how they work) and a poor connection or wrong type wire could mess that up. All that said, some on the board do this splicing on a regular basis and report good results. Compared to the stock unit you could almost try it and if you don't like the results buy a Walker unit and come out pretty close to even. Good luck.
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