1983 Mark VI car wont start


high i have a Lincoln mark vi and im having issues with starting it. I have put a pressure tester on the fuel rail and it reads 39 psi like it is supposed to but it bleeds off in the matter of seconds i have checked for leaks in the fuel system and replaced the fuel filter but found nothing. the only way to get it started is by putting carb spray into the throttle body. The car seems to do this when it is cold out. I have even tried turning on the ignition multiple times before trying to start it and it still does not work. Im trying to find out if maybe it is a bad check valve in the fuel pump but thought maybe some one could give me a little better information about this mark VI before i start dumping money into it. It also has had a tune up in the past 10,000 miles so im ruling out any electrical problems and it turns over just fine but it will not start. also the relays come on but im not sure if the computer may be in a fail safe mode where i would need a diagnostics code reader to clear codes. when i do get the car started though it runs and drives fine its just that initial start up and its getting worse as its getting colder out side. any feed back would be appreciated..