My honda Temperature is below the middle but the coolant reservoir overflows and spill through the top. I can ihave the car running idling now problem but once starts driving for a few minutes start puking coolant.i put a new thermostat. You do here whining noise when driving could be water pump but no coolant coming from front of engine. Thanks

 

The radiator cap is supposed to hold some pressure ( 15 lbs. ? ) If it's worn then it'll go into the reservoir which has a pin hole and isn't supposed to hold any pressure , if the cap is good and thermostat is good and it still pukes when you drive it may be a blown head gasket .

 

I put new radiator cap and reservoir but used the old hose for it. Ill have to check the hose and do a coolant pressure test. Thanks for the help. I'll update you soon