Volvo Repair: 1993 850 volvo, mass air sensor, cam sensor

Question
My  volvo  dies  while  driving  or  at  a  sto p light  for  no  apparent  reason.  The  dash  lights  come  on  too.  I  have  to  wait  at  least  two  minutes  before  I  can  successfully  turn the  engine  over.  It  seems  more  often  when  its  warm.  Could  it  be  the mass  air  sensor  or  the  ECU?   Maybe  a  change  of  fuel  filter? The check  engine  light  is  on  as  well.  How  can  I  read  the  codes?  Any insight  would  be  appreciated  as my budget  in  tight.

Answer
Here we go again with the Magic fuel filter cure.  Read the codes by putting the pin in number 2 and hold button for 10 seconds.  (you need to do this with key in on position) write the flashes on a piece of paper.  After the flash is done push putton again.  Do this until  The same code comes back, Example:  1-2-1. Clear the code by holding the button for 10 seconds after the last code is read.  Do this on the 6 also.  What probably is going to come up is a Cam sensor code.  Roger