1998 GMC Sierra 2500 p/u starts and dies when warmed up

bad need of a tuneup? like new spark plugs, ?
172 , is 02 rich/ lean warning. this one is low oxy for rich.
this code can just be a victim. for sure , with misfire.
means 02 sensor stuck at rich,
what is water temp in engine coolant, at failure? less than 150F?
could be lots of things.
leaking injectors, bad fuel.
injector sticking> causing misfire.
id use a scan tool and watch all sensor when it fails.
too high fuel pressure.
misfires cold, but only luke warm cold starts not fully cold.

just one DTC, no P0300 or 30x misfire codes, not even P0300 pendings?

Check the primary and secondary resistance of your coil. Also check spark plug wire resistance. The coil will short out when it heats up if it is going bad.

check for vacom leak on engin intake

my 1998 2500 sierra fuel pump has been replaced inside the fuel tank already,now a year later it's dying again when driving ,like it is not getting fuel at all! I have a 5.7L engine, is there a in line filter somewhere?

needs a thermastat or your low on coolant

The anti thieft system is keeping it from running.

You always add transmission fluid while the car is at running temps because transmission fluid expands when it's hot.

Sounds like the cam positioning sensor. I have a 2002 GMC 2500HD 8.1L and this happened to me. Hope this helps.

THERMOSTAT REPLACE IF NOT SEE IF HOSES ARE CLOGGED SHOT OF AIR COULD HELP OR DISSCONNECT BATTERY CABLE 10-15 MIN CONNECT BACK TRY HEATER

30-40 psi of oil pressure is fine for many vehicles including your GMC. I am assuming that the truck has more than 100,000 miles on it and still has the original engine in it. By rule of thumb you only need 10 psi per 1000 rpms in a typical street driven engine to give adequate oil pressure to keep the bearings from oil starvation. The oil pressure is typically higher when initial start up occurs because it is more viscous due to the temperature of the oil as the engines oil warms up the visconsity thins out and the oil flows more smoothly. The drop in oil pressure is a normal occurance. Above 45 is more than required for a daily driven street engine. I believe that the specs on that engine only list 30- 45 psi.