1993 945 non turbo
cold weather package
California car
131,000 miles

On cold days under 50 degrees after sitting for more than 8 hours my car has a very hard time starting. It just cranks for a couple of min and then it does this start and stall thing for a few times before it will finally start and run real rough for about 15 seconds. I can spray some starting fluid into the intake and get right to the start and stall part right away. Once the car has been driven or it's a warm day the car starts normal. I was told to pipe propane along the vacume lines and along the intake to see if I would get a change in RPM's and find a possible air leak but no such luck. Does anyone have any idea what could be causing my baby to feel sick?

*********************UPDATE*************************

I have checked all vacuum leaks again and again found nothing. Everyday it's cold now and needs to be started with starting fluid. The check engine light comes on every time I go through this. The code it shows it 1-2-3. I have replaced the cap, rotor, wires plugs and the temp sensor on the back half of the block. My temp gage on the dash failed last year so I'm also going to change that temp sensor too. The car runs and drives wonderful and will even start normal once the weather is warm or the engine has been run for a few min. I am open to any ideas as how I can fix this. It's going to be snowing very soon and I'd love to get this fixed.