If there's one complaint I have about the SC its that the A/C systems in these cars sucks. This is now the third fall/winter season in a row that my heater has decided it doesn't want to work anymore.

What's ridiculous about this years problem, is that, what its doing is exactly opposite of the problem it had when I first got the car.

The problem I'm having now is that the heater just blows cold air when the car is at low rpm or idle. I have to keep the rpm above 2500-3000 to get any heat.

Ive replaced the majority of the heating and a/c system on this car and the heater worked perfectly earlier this year. I'm really getting sick and tired of this.

 

Mine does something similar. Last I tested it was before it got cold and it still did it. Mine just takes absolutely forever to blow warm air. The valve is opening and the heater core hoses are hot, but it takes a long time for warm air to come out. Dunno if the core just takes a while to warm up or what.

 

You need to top the coolant off. This would come up in search. Pour it full until it overflows then cap it. The system will purge itself. Hence why the cap is tension spring loaded and there is a tube beside it.

 

https://www.clublexus.com/forums/sc-...sometimes.html

one of so many.......

 

Coolant is topped off. That was the first thing I checked.

 

my heater aso quit on me recently ,,ill try the coolant today to see if its topped up, but if not what are the leading causes of failure with the heater do you guys know?

 

did u figure your problem out matt?

i topped up my coolant but it still doesnt work , any advice on what to do next?

 

Matt, I have the same problem with my 2005 RX 330--great heat while running, high RPM's---when idle, cool air--Any ideas???

 

I bypassed the stupid vsv...have had hot air since october

 

Thanks! Will give it a shot.

 

By bypassed I mean the coolant goes directly to the heater core btw. Not the vacuum line swap trick

 

most common problem is the heater control valve.


Posted from ClubLexus.com App for Android

 

I've got the same/similar issue with my 95'. The heater control valve is working, both sides of the inlet hose are hot but the hose coming out is not. Both of the radiator hoses are very pliable, as in I can squeeze them like they are empty. They are hot, but not as hot as I'm used to. I've got coolant topped up at the 17mm fill plug at the t-stat.

My thoughts-
1. I've got air in the system (most likely since there's no pressure in the rad hoses)

2. Heater core is stopped up

I've been looking for ways to get the system full and I'm about to fill the rad with the top hose off. Then I'm out of ideas.

Another thing is that the temp gauge never gets over two notches high.

results to follow

 

Fail! I may not have a thermostat in there or else it must be stuck open. So I removed the top hose from the rad and it had coolant in it, no much but some. As I filled the top hose into the engine an equal amount would dump out of the radiator. Shouldn't the t-stat stop this from happening? The engine was cool. I guess I gotta find a local dealer and get myself a new t-stat and gasket for starters.