[Kistle]

There is nothing in a '73 MFI motor that would act as a safety kill switch on the fuel or ignition because of oil temps.

Like Wayne, I believe this to be fuel, or at least mixture related. A few questions:

1) What RPM does the car idle at when "cold". How about when "warm", but not "hot"?
2) When it dies, does it stumble for a bit and then die, or does it just die abruptly?
3) What condition is the air filter in?
4) What is the ignition timing set at?
5) What kind of electric fuel pump is fitted, and where is it located?
6) Is there a thermostat fitted on your MFI pump?
7) Can you post a picture of your motor?

Let's start with these. Also, I would NOT start randomly trying to adjust the mixture setting on your MFI pump. You do not have a baseline, and it is VERY easy to get that out of whack to a point where you will make your situation worse if you do not approach this systematically.

JA