Volvo: 1994 volvo 940 trouble starting, 1994 volvo 940, volvo 940

Question
I have a 1994 volvo 940 with over 180,000 miles on it and i have been having trouble getting it to start.When it does start it will only run for about 5 or 10 min then it will stall and i will have problems getting started again.i have taken the wire that runs from the coil to the distibutor off and put it next to the engin had someone turn the key and there would be a spark sometimes and other times no spark. i have changed the coil,rotor and distributor cap but still have the same problems.I had someone come over and take a look and he put a tester on the coil and he said it had power and he also put the tester on the power stage wires and he said that had power but he told me he thinks the power stage is bad because it was not sending a signal over to the coil to get a spark is he right or could it be something elese that is wrong.I don't understand that if they both have power how can the power stage be bad if you could help me out i would really appreciate it. thank you

Answer
Robert,
Read the fault codes and see what they are. You may have a posted code for the flywheel pick up. If that is not sending a signal there will be no spark. If there is not a code for the pick up then try a power stage. There is not a fault code for the power stage. You might also look at the pick up wire and if it is frayed replace it.