Heater. Not As Hot As It Should Be.

[CLightning]

...even when the temperature of the engine is warm, when I turn the heater on, for example on "MAX," the air coming from the vents is only warm. It's not as hot as it used to be. Am I facing a big problem here? What seems to be the problem? Thanks.

[SKperformance]

the valve on the firewall with a rod is the usual problem

[Marty Witt]

Do you notice it is colder when you come to a stop?? Add a little anit-freeeze!! Mine would blow cold when I came to a stop and warm when I began moving. Someone on this site said to add a little anti-freeze. Even though the level looked OK, I added about a pint and a half and voila, it blows warm when stopped. But, it also blows warmer when I'm moving also. So, double check your anti-freeze and possibly add a little juice.

[CLightning]

Thanks. I will look into both suggestions. However, I added antifreeze just the other night. I filled up the coolant reservoir and topped off the radiatior as well. Same deal, just mostly cold air and intermittent warm air.

I also did a general search thru the net and most people suggested:

1. clogged heater core.

2. blown head gasket.

3. faulty thermostat.

hmmmmm.... I hope to God it isn't #2!

BTW, do you guys think that me recently switching from fossil to 10W30 synthetic oil is related to this new problem? The car has about 120K miles on the odo.

Thanks.

[dmurphy]

YOU PROBABLY HAVE A DEFECTIVE HEATER CONTROL VALVE. IT IS NOT HARD TO REPLACE BUT THE PART IS EXPENSIVE.

[mehullica]

the heater control valve on this car is has an electonic VSV valve. They do fail. Apply vacuum directly to the valve and it should blow hot air. If it does, buy a new VSV valve

[ford212.809]

;)

the heater control valve on this car is has an electonic VSV valve. They do fail. Apply vacuum directly to the valve and it should blow hot air. If it does, buy a new VSV valve

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I am putting my money on a "malfunctioning thermostat." I have replaced MANY over the years for the same reason you mentioned.

[cruznroadking]

I agreed that it's most likely the heater control valve. It's common on earlier SC's. First inspect it for any external leaks, then check if the linkage is out of adjustment, which may cause the valve to open up all the way, then perform the vacuum test as recommended by Mehullica.