Is there a mechanic in the house?

[mr9iron]

My wife has a 2004 Toyota Camry and I noticed the last couple of nights that when we come to a stop that the heater starts blowing cooler air. However, when we start driving again the heater starts blowing warm again. Any ideas here?

[Satori]

Possible vacuum leak maybe.

[Glove]

Heater core is clogged

If the system has "orange" coolant in it (mostly Dexicool in GM vehicles) that stuff is evil. It turns into a red rock hard substance after time.
You can try to flush the heater core or you can replace it and flush the whole sytem replacing with new coolant.

OR
water pump is not pushing as much as it should (not very common, they just start leaking, make horrible noises or lock up)
Or
the whole cooling system is getting gummed up and need a good total system cleaning.

I still bet you could flush the heater core and buy some time.

[surfjeepzx]

Check the coolant level in your radiator. You may have a problem with a sticking thermostat in that it's staying open. Have you noticed lately the car takes longer to warm up?

[mr9iron]

Originally posted by surfjeepzx
Check the coolant level in your radiator. You may have a problem with a sticking thermostat in that it's staying open. Have you noticed lately the car takes longer to warm up?

No, we just started noticing this over the last couple of days.

[mr9iron]

Originally posted by Glove
Heater core is clogged

If the system has "orange" coolant in it (mostly Dexicool in GM vehicles) that stuff is evil. It turns into a red rock hard substance after time.
You can try to flush the heater core or you can replace it and flush the whole sytem replacing with new coolant.

OR
water pump is not pushing as much as it should (not very common, they just start leaking, make horrible noises or lock up)
Or
the whole cooling system is getting gummed up and need a good total system cleaning.

I still bet you could flush the heater core and buy some time.

Um ok, how exactly do you flush the system? I'm not a mechanic so give me instructions that are clear and concise.

[Glove]

low coolant = over heating issues most likely at a stop
Sticking thermostat open= constantly low temps regardless of RPM
sticking thermostat closed = overheated engine

When you come to a stop the water pump slows down and dosnt have the pressure to push through the lines unlike like when you are turning higher RPMs and the pump pushes with more fush and pressure.
Its a restiction issue.

[Glove]

well I will try... been a while since I was under the hood of a Toy.

Somewhere on the back wall of the engine compartment, usually on the passenger side you will find two rubber lines that are connected to a couple of copper or aluminum formed tubes that go into the car to the actual heater core located behind the dash. protruding from the wall on the engine side one line is input and one is out- just like a little radiator.
*if you can remove both hoses at the intake (on the engine) you will end up with two open ended hoses connected to the heart core.
Get you a garden hose and push water into one line for a few then into the other line (the lines going to the heater core).
its a mess and you dont want to get water all over an alternator, fuel delivery or electrical stuff.

little confusing, sorry.

[mr9iron]

Allright, I checked the coolant level in the overflow and found that it was somewhat low. I then took the radiator cap off and did not see coolant at the top of the radiator. I guess it's time to go to walmart and grab some antifreeze. If I remember right, I'm supposed to add a 50/50 mix directly to the overflow and not the radiator. Should the car be running when I do this?

[Glove]

if the engine is hot yes, you need to leave it running while you add the coolant.
If the engine cold, you can top off the radiator with the engine off.
Strange you were low on coolant and not showing a high temp on your gage.
Must be in colder weather and not low enough to have caused the engine to get hot.

[mr9iron]

The weather is really cold right now!!! Do I fill the radiator all the way to the top? I know these seem like silly questions but I am not a mechanic by any means.

[Glove]

yea go ahead and fill it with a 50-50 mix of water and coolant
(not straight coolant)
Also can fill the resivior completely to the top. When the radiator gets to full pressure it will push air and a little coolant from the overflow tube so dont think its a leak right away. This is a way to purge the air from the system.

[mr9iron]

Originally posted by Glove
yea go ahead and fill it with a 50-50 mix of water and coolant
(not straight coolant)
Also can fill the resivior completely to the top. When the radiator gets to full pressure it will push air and a little coolant from the overflow tube so dont think its a leak right away. This is a way to purge the air from the system.

I plut the coolant into the radiator and put a little in the resivor as well. It was about a half of a gallon low. I'm really not sure why it was low but I will keep an eye on it for the next couple of days. I think a trip to the mechanic may be in order. The car is a 2004 and it has 66000 miles on it. I took it for a spin and everything seems ok for now.