cnorman

I have a 2004 RX 330 with around 134000 miles. Back in the summer I noticed that my A/C was not blowing out as cool or as strong as it used to. Now that the weather is cooler I have noticed that my heat is not blowing that well and is not warm. I sometimes experience a long defrosting time or only have hot air blowing out on one side of the car and even defrosting only on one side. It is like sometimes the air will be cool and strong and a few minutes later weak and hot air is blowing out. With the heat it is sometimes really warm and gets the car warm on the inside and a few minutes later blowing ice cold air. Around the same time, I noticed that my car was running hotter than normal. It continually stays at the halfway point if I am driving constantly or not stopped very long. However, it does start to run hotter if I am in traffic, idling in a drive-thru, at stop lights, and even when I go up hills. Do you know what could be causing this? Is it all related? Where should I start with fixing the problem?

Lexiluv

Same problem with my 2005. I am getting the engine thermostat replaced on Friday. I'll let you know if that solves the issue.

LSBen

Do you hear sounds as if a gerbel or hamster is crawling under your dash making scritch scritch sounds? If so, I suspect your Air Mix Servo motors are going bad. There are a few small plastic motors under your glove box, 1 that controls temperature and 1 that controls which vent air blows out of. There are DIY instructions on this site. Just do a search on Servo Motors and RX and you will find tons of posts, pictures and instructions. My RX has hamsters running loose under the dash but the heater and AC still works fine so I wont go hamster hunting at this time.

Here is one such post

https://www.clublexus.com/forums/rx-...old-air-4.html