20 Most Recent
- Page 2 Questions & Answers
Why does heater blow lukewarm air that turns cold?
An air bound heater core can cause this. A thermostat issue would cause it to overheat quickly (stuck shut) or cause the engine to take a long time to get up to normal operating temperature (stuck open).
Try this after the car has sat over night and is COLD.:
Top off the coolant RESERVOIR to the COLD MARK with a 50/50 mix of coolant and water when the engine and coolant are COLD. Replace the reservoir cap.
NEVER open the radiator cap when hot!!
Open RADIATOR cap - WHEN COLD - and top off radiator with the same 50/50 mix of coolant and water to just under the inner lip of the filler neck.
Start engine, turn heat to HOT and FAN to HIGH.
Watch the coolant level in the radiator. Maintain the level of coolant as close as possible to just under the filler neck lip. It is expected to fluctuate up and down as the thermostat opens to flood the radiator - and be pulled into the engine block. The more variation in the high and low indicates a fair amount of coolant has been lost. After the engine has gotten hot, you should feel hot air coming from the heater. Check the radiator level once more, top off and replace the radiator cap.
If still no heat, there may be a clog or restriction in the heater core hose. A cooling system flush should fix this, but can cost a few bucks at a Jiffy Lube or similar.
If you're losing coolant - that could be an indication of a leak (see puddles where you park?) due to a bad hose clamp or hole in a hose ($) or a bad gasket ($$$) or cracked engine block ($$$$). Look for white "smoke" (steam really) in the exhaust after the engine has warmed up to indicate that the coolant is entering a piston due to a gasket or block issue.
on Oct 08, 2015
Not finding what you are looking for?