Question about 2005 Lexus SC300
I have a 1992 Lexus SC300 with the heater blowing cold air. I have changed the thermostat and that didn't work. The engine does not overheat. Last spring, the heater would blow heat sometimes and sometimes not. It seamed like if the car ran for a few minutes before you turned on the heat, it would blow heat after the car warmed up. If you turned on the heater immediately after starting the car, the heater would not blow heat even after the car warmed up. Any suggestions on where to start? I have shop manuals.
With the car warmed up,feel the heater hoses,are they both warm/hot near the firewall in the engine compartment?If they are both warm/hot,then the heater core should have circulation through it and it may be a "blend door" issue in the heater a/c assembly.If they are not warm/hot then the heater core could be dirty and plugged up and needs to be flushed.
If the above does not help,a drain and vacuum of the cooling system and vacuum refill will remove any trapped air.
Sometimes,clamping off the top rad hose and holding the engine rpm at 2000 rpm will force trapped air out of the heater core.(Watch temp gauge when trying this)
Lastly,a NEW thermostat doesn't mean its working correctly.
Posted on May 19, 2017
A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
replace the power steering pump. make sure you get crush rings for the hoses too. dont use stop leak stuff either because it WILL clog the filter in the power steering rack and then youll have to replace that too.
Posted on Aug 23, 2009
Tips for a great answer:
Toyota 4Runner: Temperature Gauge Sensor http://technoanswers.blogspot.in/2012/04/toyota-4runner-temperature-gauge-sensor.html
Temperature gauge sits over half way mark? http://schematicsdiagram.blogspot.in/2012/04/temperature-gauge-sits-over-half-way.html
Heater blows intermittently and temp gauge goes erratic?
------------- No heat on Oldsmobile Silhouette? http://technoanswers.blogspot.in/2012/02/no-heat-on-oldsmobile-silhouette.html
Temperature gauge does not move and no heat when heater is ON? http://technoanswers.blogspot.com/2012/01/temperature-gauge-does-not-move-and-no.html
Temperature gauge keeps fluctuating up and down close to red? http://technoanswers.blogspot.com/2012/01/temperature-gauge-keeps-fluctuating-up.html
----------- Temperature gauge on the dash quit working on Pontiac Grand Prix? http://technoanswers.blogspot.com/2012/01/temperature-gauge-on-dash-quit-working.html
Dodge neon gauges not working? http://technoanswers.blogspot.in/2012/02/dodge-neon-gauges-not-working.html
Heater blows cold? http://schematicsdiagram.blogspot.in/2012/02/heater-blows-cold.html
Heat blows cold on drivers side and hot on passenger side? http://schematicsdiagram.blogspot.com/2011/12/heat-blows-cold-on-drivers-side-and-hot.html
1992 Lexus LS400: Engine overheats, Antifreeze out of reservoir and heater Blows Cold Air? http://whatisbyme.blogspot.in/2012/05/1992-lexus-ls400-engine-overheats.html
These details will help.
Nov 22, 2012 | 1997 Ford Taurus
Feb 21, 2011 | Lexus SC 400 Cars & Trucks
Heater cold when at idle: Try stopping on a steep incline--does the heater stay warm? If yes, what you have is an air bubble that hangs at the heater hose until pressure from the water pump blows thru it as the engine speeds up. Park on an incline, open the radiator cap, run the engine until the thermostat is open, and fill the radiator to the neck. Wait until the level stops dropping and make sure bubbles don't continue to come up. If they do, you may have a blown head gasket that will keep forming these bubbles until you change the gasket. Please let me know if you have questions.
Dec 22, 2010 | 1992 Lexus Sc 400
Jan 15, 2010 | 1993 Isuzu Rodeo
Jun 17, 2009 | 1992 Lexus Sc 400
Jan 27, 2009 | 1992 Lexus Ls 400
Dec 05, 2008 | 1992 Jeep Wrangler
333 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: