Sounds like a bad WUR, but like everyone else is saying, if you're not going to do the work yourself, you need to take it to a Porsche mechanic (not neccesarily a dealer). If you go to the average mechanic, you will spend more on replacing parts that don't need replacing than you will on the difference in labor rate. If you don't have access to a Porsche mechanic, I recommend buying CIS pressure testing gauges and a Bentley manual, and then spend a couple of hours searching this forum for similar problems and solutions.

There are lots of threads on this. This is very common on old CIS cars, especially as cooler morning temps start up again. Most common causes are the WUR as David says, the AAR, or even a too lean mixture setting.

http://forums.pelicanparts.com/showthread.php?s=&threadid=119700&highlight=cough+ sputter

this was my experience. Sounds exactly like what you aer going through. I will go out on a limb and say this thread will fix your problem.

-I still am kicking myself over this ....

I had the same problem once. My mechanic forgot a T wrench in the upper back end of the engine (TOP SID

jpc

This 20 year old thread just helped me diagnose and fix my SC. Was running like crap, and dying shortly after ignition. I had recently done a bunch of service to CIS and fixed some vacuum leaks, so I had already tested several components. The cause of my issue was a bad wire in the driver's door for the dome light switch. It was popping the fuse that is used by the lamda unit relay. Who would have thought a dome light would stop the car from running? This community is such a great resource.