will not start on 1991 Volvo 940

changed plugs, wires, engine coil, dis.cap and button, fuel filter, but it will not start, trys to start, but wont

2 answers
You may have a failing clutch. Check power to the clutch and try to duplicate the symptoms, then check the signal to the A/C Clutch to see if it's still getting power.
Or have a shop diagnose this for you: http://repairpal.com/directory?address=33534&car_brand_names=Volvo
If you get some codes post them and I can assist you further.
I was having a similar problem with my 94 940 and I just recently replaced my ignition modulator and the problem was illimulated. $140 for the part, it is real easy to replace. Read repair manual before repairing, real delicate part.