Heater is hardly blowing out, and it's not warm or hot air--but cool. Also--side windows fog up, and don't seem to defrost.
Heatercore is done
When the engine is cold,check the coolant level.
Make sure it's on max.
===
A coolant system should be flush every two years.
===
If you did a coolant flush recently then air pocket can be the cause of the un-even heating problem.
The DIY method is to drive you car onto a ramp or a steep hill.
Iet the engine cool off and top off the coolant tank.
Set MAX heat + MAX fan
Let the engine ran for 20 minutes wih the cap off and the trap air will escape from the coolant reserve tank,
Check coolant level and top off coolant when the engine cools down.
A shop will charge $75+ for this but using an air operated excavate tool!
========
A car with over 90K miles may experience linkage problem to the heater control valve.
The heater control valve (near the firewall) may be stick over time.
Open the hood and move the heater to max and min. Back and forth.
Clean and lube the linkage with WD-40 to free the heater control valve.
If it's a vacuum type heater control valve then cash for leaky vac. hoses.
=======
Move the fan switch back and forth to re-new the electrical conductors.
Pass a vacuum over the control panel to prevent dust build up behind the console.
SOURCE: 1999 Volvo S70 heater and defroster blowing "fog"
suspect leaking heater core.check coolant level.
560 views
Usually answered in minutes!
Heater in my LW300 6cyl wagon blows air that is barely warm when cranked. tried flushing, new thermostat, no luck
I have the same problem.My heater is not working at all and the windows fog.
×