Volvo: 1998 S70, wheel hub, noise problems

Question
What does the Longitudinal Accelerator Sensor do? How hard is it to replace myself? Also a rubbing sound coming from front left tire area. Nothing I can see visually wrong with it. When I turn the wheel to the right, it quiets. Any suggestions on what to check for the problem? Could it need new bearings?

Answer
Damien,
The sensor in under the car toward the right side bolted to the sub frame. Just unbolts and unplugs.
If the tire is not hitting under the wheel well area then could be axle noise or wheel hub bearing. Noise problems are sometimes hard to find. You may have to replace some bearings and axle to be sure.