Okay, i'm a newbie and i have only been driving my volvo for a year or so. I don't really know much about anything really. I was stopped at a light a while back and my car suddenly got really loud. I get it home and find out that the oxygen sensor has fallen out. I try to stick it back in and i find that the threads are completely chewed up, unfixable... so to speak. I took it to a local volvo specialist, and they charged me 145 bucks just to look at it and tell me it was going to cost me an additional 300-400 bucks to have them fix it. I know when im being taken advantage of, and this guy was tryin to screw me. My point is, i know i shouldn't try to drive the car like it is, and i don't have much money. So i bought a used manifold off of a dealer, and decided to do it myself. I don't really know how to do this, and the chilton repair manual doesn't help me much. I know i need new gaskets, and not too much else. I need any help i can get, my knowledge is limited. Thanks for helping and sorry the post is so long. Jason