tikatoy1995

If the aluminum water tubes to the heater core are getting hot as the motor warms up, the only thing that could prevent hot air from entering the cabin would be a mechanical blockage of some type. I suspect what you are seeing is only a partial movement of your old Air Mix servo and not full-range operation. That was what I was getting on mine. Unless there is a squirrel nest in the duct work, I think it has to be the Air Mix servo. I guess it is possible that the signal that controls the servo could be faulty but I've never heard of anyone having that particular problem without other symptoms. I'd suspect you might have display issues if that controller had failed but just guessing here. Given the age of the OEM servos and the known prevalence of this particular problem, I'm putting my money on success if you replace the servos. Be sure the servo is correctly connected to the linkage. It's pretty obvious but you can install it incorrectly. Don't ask me how I know.

thanks for that, just wanted to be certain as most posts indicate movement issues.. I'm ordering the part now.. if anyone else is interested.... i found this site .. the cost for air mix servo is $152.00 with free shipping..@ www.mylexparts.com. I'll update after installation. thanks.

I agree with your approach. If you are going to go to the trouble of removing the Air Mix Servo then I would replace it. After I replaced both of mine I did disassemble the servo and you can 'clean' the contact surfaces but I think the problem is more with wear than with dirt. I suspect any fix obtained by "cleaning" the servo could be short-lived and then you'd have to go through ALL this again to install the servo that you'll wish you had installed when you had it out the first time.

Just go easy and use your good judgment on getting those screws out. It really isn't as hard as it looks but it could require a trip to the tool monger to get the right screwdriver and that would be money well-spent.

Let us know how it goes.

well I FINALLY got that air mix servo out!!! .. before I removed it, i checked to see if all the movement was there, and it is. before i buy the replacement I just want to be sure.... even if there is movement with the handle going up and down when told, it can still refuse to give hot air???? because it seems operational and I'm wondering if i'm not getting heat and its due to something else. rather spend the money on what I actually need... thanks.. I know I've been slacking with my repair.. but now that its starting to get cold, I need to move on this...

If I remember correctly, the servo you are having trouble removing is the Air Mix servo. The easier one is the Mode Servo (floor, vent, defrost, mix). The air mix servo is the one that actually allows air to flow through the heater core and into the cabin. I was able to remove my Air Mix servo through the use of a thin screwdriver and probably a little "flexing" of the water supply/return pipes. It seems that I was "closer" to getting the screw driver head to engage more on one side of the pipe than the other so I approached from that side to flex the aluminum water pipe - CAREFULLY. The screws are seated in the plastic housing and don't require that much torque to loosen and once you get it started out it comes easily. Once I made the decision to "get it out or bust" the servo screws came out with little effort and there were no adverse effects (read: leaks) from flexing the aluminum water tubes as required. The tubes were not flexed sufficiently to impart a permanent bend; just a temporary displacement to allow the screwdriver to do what had to be done. NOTE: when the motor is warmed up, if you feel those aluminum tubes and they are HOT, in all probability the only source of your problem is the Air Mix servo. If you look at that servo and run the cabin temperature setpoint from Minimum to Maximum and there is little or no movement of the air mix servo positioning arm, the likely culprit is the air mix servo.

Hope this helps. My advice is worth everything you're paying for it.

Not what I wanted to hear, but I'll try again to pry out that nasty screw and think i'll just replace the servo rather than doing maintenance on it. thanks.

2000 RX300 Cooler Unit Part Numbers

Hi Filehorse, maybe you can help me out here. I did a prior post about that clicking noise and no heat and was told the "servos". I got to the first one, i guess that would be the airmix and simply can't remove the second one just behind it, where the two pipes are... my problem was the clicking and no heat. after removing and cleaning the air mix servo, the first and easy one to remove. for now, i have no noise and I get very light heat at Max temp. before i put my glove box back, do you think replacing this first servo would give me max heat, or is the heat controlled by the 2nd one, (which I can't get to). all my vents are giving good air output and always did. the a/c works great, just very low warm air from heat. any suggestions would be appreciated.

bett

I'm assuming you cleared the code and it keeps coming back?

yes, i forgot what the code was.. B101 maybe???? it was for knock sensor and yes, it keeps coming back.

Hi, I have a 2000 RX300 with less than 80K miles on it. Like a dope, when the gas prices got really high i put regular gas in the car. after a few months with a lot of knocking i thought i'd better go back to premium. the knocking has stopped and mileage has improved. BUt now i have the check engine light on. while driving at around 60mph my rpms are at 4000 and it doesn't feel like it going into fourth gear. My mechanic, who has the same car, changed his tranny and still had the check engine light on. he said that after he changed his knock sensors the light finally went off and suggested thats what i do rather than go directly to the tranny. the code does come up as the sensor.

Does anyone out there know if replacing the knock sensors will actually make my car shift into gear? He quoted me $650, which i think is reasonable and will also have my spark plugs changed out while he's in there. but has anyone else had this problem?

thanks

I found a website that seems to be the least expensive for the ceramic akebono brakes....

www.rockauto.com although they don't have the brembo rotors they have other brands.

Hi, it seems my 2000 rx300 needs brakes and to have the rotors cut, although i heard somewhere sometime ago that i shouldn't have the rotors cut and to just replace them. can anyone tell me if having them cut is okay and what type of brakes are the best to buy. thanks

thanks for the assistance !!!!

bett

At this point I'm having a hard time totally trusting Lexus. they said I needed all four replaced as well as all four brakes. a few months ago my mechanic replaced my brakes and said there was nothing wrong with my front rotors or brakes and didn't replace my front brakes. Now my rear brake(s) are sqeaking and I was going to go back to my mechanic and I think he did say I needed rotors. Would you suggest sticking with OEM brakes as well?

bett

lexus people told me they can't be cut. I guess I should have known better. thanks for the help.

bett

Hi Steviej...actually no special reason for not going with oem parts. I just figured since its my brakes and Lexus rotors can't be cut, I may as well spend a few extra dollars and get something that will last longer. I was thinking brembo rotors. I've also read that the cross drilled takes away from braking power. I've ordered the Yokohama geolander tires GO52, which I read on this site was excellent and I know I need new rotors and brakes because they whistle a nasty tune while driving. thanks

Bett

Hi, I need to change the rotors and brakes on my 2000 RX300. does anyone have any opinion on whether I should get cross drilled or just slotted rotors. I do not drive off road. also any opinions on Kevlar or Axxis brakes? thanks much.