Classic/Antique Car Repair: 86 jaguar xj6 4.2 s 6, coolant temperature sensor, throttle position sensor

Question
my car starts up, but put her in drive she stalls. after a good time of trying like starting in neutral then to 1st she will run, well ill move to 2nd go about 1min and  she sounds like she is out of gas or getting to much,so i will put her back into 1st and repeat the same ,but if i stop at all she dies . please   i love  my car

Answer
Wow, in the age of electronics there could be so many things acting up. Here is the list that could cause the problem:
Fuel pressure and flow
Intake air metering system (air flow meter)
EGR Valve
Coolant temperature sensor
Computer
Fuel filter
Throttle position sensor
Plugged Catalytic Converter.
The case is not hopeless but unlike the older cars that could be diagnosed with a test light, a good ear, and simple tools, this one is probably going to take some one checking it with some instruments. The price paid for that will be less than throwing parts at it in a hope and guess game.