Hi......... new to the forum.....

my daugher has a 1998 sunfire.... has no heat....
she has replaced the thermostat.... blows cold air...
engine runs fairly hot when she is idling... when she acclerates
the temp. gauge starts to come down...

does anyone have any ideas....
appreciate a reply....


thanks..... :confused:

Air bubble stuck in the system and/or low coolant. Leaking head gasket forcing air into the coolant will also cause the same symptoms. Heat gasket problems on Cavaliers is definitely are not rare.

Hi......... new to the forum.....

my daugher has a 1998 sunfire.... has no heat....
she has replaced the thermostat.... blows cold air...
engine runs fairly hot when she is idling... when she acclerates
the temp. gauge starts to come down...

does anyone have any ideas....
appreciate a reply....


thanks..... :confused:
just read in my Haynes manual that"when heater mode is activated a flap opens to expose the heater box to the passenger compartment" are you sure this is happening?

You might have the heater core plugged up a bit. You can have the cooling system reversed flushed with the heat setting turned to hot. This will probably help a lot and at the same time will eliminate any air bubbles that may have formed in the cooling system. If that doesn't help, then most likely you will need a new heater core. This will be costly to replace mostly because of the labour required to remove the dash of the vehicle.