Ts800 runs for short periods of time then stops , but fires rite back up ?????

SOURCE: can not find rite firing order car back fires

165432 for a 6 cyl. 3.4litre
18436572 for V-8 5.7litre
These are for the stock engines, If you have upgraded to the LS I would need to know which one.

SOURCE: The car will run for a short period and then stop.

sounds like a fuel pump reley to me

SOURCE: 1998cav 2200 motor runs great after driving 10

HA hA At least you have a sense of humor. Check the timing

SOURCE: Bad misfire

run the fault codes as misfire can be from injectors , low fuel pressure and ignition problems
all temp gauges will show a rise on stopping an engine as there is still residual heat in the block and heads with no water circulation and cooling
the fire from the exhaust indicates an exhaust valve is not closing properly so a compression test would be in order to check for valve problems or hydraulic follower problems