Heater Not Working

[4howard]

When I stop my 95 LS400 at a light the air temperature from the heater begins to fall and becomes completely cold. At cruising speed the heat is fine. Coolant level is full and air has been bled. Help it's cold in there!

[landar]

When I stop my 95 LS400 at a light the air temperature from the heater begins to fall and becomes completely cold. At cruising speed the heat is fine. Coolant level is full and air has been bled. Help it's cold in there!

Your symptoms are classic air bubble(s)/low coolant. How did you bleed the system?

Have a look at this thread ---> http://us.lexusownersclub.com/forums/index...8&hl=heater

[yardbuzzard]

When I stop my 95 LS400 at a light the air temperature from the heater begins to fall and becomes completely cold. At cruising speed the heat is fine. Coolant level is full and air has been bled. Help it's cold in there!

Flush the heater core extremely well if bleeding the system does not work.

[PhoenixTech]

All of which is good advise. Don't overlook your heater core. If it is partially clogged then it can cause the same symptoms. you can run a chemical cleaner through it and see if that helps. I have noticed that the thermostat can be at fault also. But if you have a check engine code for the water temp sensor that may be the problem. first thing, makes sure your coolant level is full.

Mouse, Phoenix Tuning