P0742 code solenoid circuit stuck on

Question

98 Cadillac seville sls codes p0302 cylinder 2 misfire
P0401 Egr insufficient flow
P1153 H025 insufficient switching bank 2 sensor. Overheating problems smells gas runs rough as hell bad gas mileage. replaced radiator, hoses, overflow tank thermostat. Still overheats uses lots of gas and oil just replaced plugs and wires in October 2016 oil change june 2017

Answer 1

When a Cadillac over heats your going to have two exhaust system exhaust going out the tailpipe and exhaust going into the cooling system that will work its way out the radiator,  You can use your nose to verify a blown headgasket, with the engine cold remove the radiator cap , start the engine a if you smell raw gas smell in the radiator you need a headgasket, there are two ways the headgasket blows, one is verified with combustion is the radiator the other water in the motor oil or coolant.