Volvo Repair: starts sometimes, flash flash flash, example 121

Question
this is my second time writing without a response.I own  1989 740gl we have put on fuel pumps,fuelrelay,rotor,spark plugs wires,and a fuel regulator. She will start at tmes even for a couple of days I never know when she will not start. I am being told that I am not getting fuel so what else is there for us to do?

Answer
I did send a response I remember this question.I am sorry if you did not recieve it.below is a copy of the question and answer I sent.

QUESTION

I own a 1989 Volvo 740gl and been having a whole lot of problems with starting. The mechanic I bought the car from has been trying to fix it . I got 2 fuel pumps,wires spark plugs,rotor,fuel regulator,ignition module and a gas relay.Once a part is put on the car will work for a while then it goes back to turnig but not catching. He is afraid it might have somrthing to do with the computer but isnot sure . I need some help I really like my car but at this rate I am ready to get rid of it I had it for 4 years. It has 127,000 miles on it now.
Answer:  if it is non turbo I would check for codes in the fuel and ignition system. below is how to check codes.then you will need to see what is missing spark or fuel when it does not start check spark first then for fuel pressure.


ANSWER

in the engine bay on the drivers side near the strut tower there is a small black box with a wire attached to it.place the wire in the terminal marked 2.turn ignition key on (not started)press the small button for 1 second and the code will be displayed as a series of flashes.a red led displays the codes.the code will be three digits.small pause in between flashes for a single number long pause between flashes for the next number.example 121 will be flash.....flash..flash.....flash.repeat three times or until first code repeats itself.to erase the code after all codes have been checked hold the button for a good 5 seconds then release the light should light steady,then press for another 5seconds.this will erase the codes. email me the codes and i will tell you what they are..socket 2is the fuel system 6 is ignition.