Sounds like the thermostat is stuck open. Try a new one.
thermostat stuck open?
follow the radiator hose to the engine, right where the hose meets the block is where the thermostat is located. Its on the the front of the engine
the vortec 4200 doesnt have an EGR system
Just follow the bottom radiator hose to where it hooks to the engine, Remove the housing that the hose clamps to and that will be where the thermostat is.
210 to 220 degrees is normal.
Between 195 and 210 degrees.
195 to 210 degrees is the normal range.
try putting anti freeze in it, you may also need a new thermostat
The one the ecm reads is located right next to the thermostat housing.
It is right beside the thermostat housing, and that is where the top radiator hose hooks to the engine.
The EGR valve on the 4.3l Vortec motors is located directly in front of the thermostat housing , near the front of the motor. Both items are located near the front of the intake manifold. Follow the coolant feed line back the to water neck/thermostat housing, the EGR valve will be the 3" canister-style object in front of that.
It is within the water outlet which is on the lower end of the top radiator hose. I hope this helps you. Mark