What is wrong with my heater???

[914lps]

Ok folks, here's one I have a 1991 Lexus 400. And I have a problem with the heater.

 When I try to heat the cabin with the a/c either in auto or manual mode, and even if I keep pushing the temperature up to the maximum temperature  I basically get no heat in my car. It does not mater where I have the air set to come out of. For example defrost setting blowing towards the windows. The heater setting blowd it down towards the floor. Also doesn't matter if the AC is on or not, for example in the defrost mode.

 The reason I say I get almost no heat is I have noticed that if I keep my driving speed up over 65 miles an hour I will get heat. But not as intense as I used to.

 Now driving at 65 miles an hour, I Drive in the normal mode With overdrive on should my rpms are probably a little over 2,500 or somewhere in there. Could be as high as 3000 but I haven't really made note of it. Also if it matters when I push the control to raise temperatures up or down it does respond with the beep beep beep.

 I have checked the heater valve in the engine compartment. When the heat is off the valve is in the closed position. When I turn the heater on the valve moves to the open position. So I'm sure the valve is opening.

 So what am I looking for? Information on what it could be and how to go about checking it. I don't know if it's an issue with my climate control unit. Or the heater volve... or what...  Nor how to check anything else 

As always I thank all of you guys for your kind help!

[jamesm182]

Could be something as simple as air in the system? Check the coolant is topped up to the right level and then allow the system to "burp" and see if that helps...

[billydpowell]

YEP, you are just low on coolant,with an airlock.. lexls.com. will tell you how to do it if you dont want to do a search..

[sha4000]

Like has been said, check the coolant level first and if it's low fill it up. 

[914lps]

Will you folks look to be right. I will keep you posted.

I checked fluids. Collent tank bone dry.

 

Shame on me! I know better and I seemed to have forgotten to check now and then. As low sensor is not working.

Added fluid and it was sucked dry.  So added more. Will check in morning with cooled car.

Put I think I found small leakage where house from tank attaches to engine. Will clean off and see.

Thank for dee help!

[jamesm182]

Good news - looks like you may have found the issue then! 

[914lps]

I took more time trying to find just where the leak is. I saw that the hose from the tank goes to a pipe. But the tube and pipe move easily.  Any one have info on where that Line hoes to.

I looked for a diagram on google but found nothing.

[914lps]

Anyone have any info?

[sha4000]

A pic would give us a reference point.

[Exhaustgases]

http://www.lexls.com/tutorials/engine/timingbelt.html

scroll down to pictures 10 and 11, it goes to the thermostat housing. It is labeled water by pass pipe.

http://www.lexussouthatlantaparts.com/showAssembly.aspx?ukey_assembly=764527&ukey_make=1082&ukey_model=15669&modelYear=1991&ukey_category=21746&ukey_trimLevel=19107

16278 is the pipe number