Volvo Repair: volvo 1995 stalling and stalling, volvo lovers, air volume

Question
we have a 1995 850 standard 4D sedan with 256K.  it started stalling & it has no diagnostic plug in (?)for info so we have had the vacuum hoses checked, fuel filter replaced, air volume control camshaft sensor replacd & the o2 sensor today.  it drove fine for 10 miles then stalled. if it sits for 2-3 min.it will go 1-2+ miles.  after sitting all nite it will go the farthest. help...we are desperate.  we are lifetime volvo lovers too but this has been a drag!

Answer
Greg and Linda, Yes there are 2 diagnostic ports over by the washer resevoir fill.  One is A and the other is B  They have covers on them.  The first thing is to scan for codes and secondly I would have the fuel pressure check. With 256K I would wonder if that is the original fuel pump in there.  For information,  I have never seen a Volvo fuel filter get clogged.  When they are changed every 30 or 60 thousand miles, they will never get clogged.  Like I said, locate the port and scan.  If your car doesnt have the 2 ports there, then the car is a early 96 and then the port would be under the ashtray where it says OBD 2.  That is also covered.  Roger