Honda Repair: 90 honda wont start n blows white smoke out the radiator, blown head gasket, radiator coolant

Question
I have a 90 honda accord lx, the car idle high n low when you start it,
last night I had to push start it but wouldn't stay on unless you pressed
the gas but would turn off when put in gear, it also started blowin white
smoke out the radiator, I knw the alternator might need to be changed
but I can't explain the white smoke or the idling, the egr valve has been
changed

Answer
Martin, white smoke = water/radiator coolant. Not good when your engine has water/coolant bypassing the head gasket. Basically you have a blown head gasket, but, only if you see it coming out of the exhaust pipe. If white smoke is coming out of the radiator fill neck area when the radiator cap is removed then you have a heating and cooling problem. This could be the radiator, thermostat, water pump or the head gasket.