If you have the same problem as mine did, its a small piece of the guide slide that broke and fell on the bottom plate. By prying the plate, you gave just enought room for the guillotine to move completly. If you want a more permanent fix, you can drill out the safety pin that holds the guillotine ...

This is regarding your starting issue, because I did have a similar problem with my 1994 850. First, the car would start when cold but not when hot. I had the code for the rpm sensor that kept coming back, and then the car wouldn't start at all... So I changed the rpm sensor (75$) and the car ...

If you can turn the key to position I, you need to free the broken tab from the lock plate. You may hit it a few times, but the best is to remove it, clear the debris and put it back (step 3). If you want a definite fix, you need to remove the extra lock pin.

OK, now, here's how I repaired the ...

I think I found the Volvo tool # 999 5497 in the trunk of my car :D

Part is removed for clarity (i.e. I took the picture after it worked)
This was done two month ago.

http://img221.imageshack.us/img221/7569/pa271922bdu8.jpg

As you can see on the picture everything is there except the bushing ...