New 100 Series heat not working. (1 Viewer)
- Thread starter 4PF RIS
- Start date
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is the engine getting up to temp?
does the rear heat get hot?
same thru all functions, defrost vent and floor?
check the tube behind the dash, to the right of your right knee, louvers in the lowerdash should have a tube attached behind there
does the rear heat get hot?
same thru all functions, defrost vent and floor?
check the tube behind the dash, to the right of your right knee, louvers in the lowerdash should have a tube attached behind there
Your heater core is most likely clogged. I just purchased a 2000 LX 470 less than a month ago and had the exact same issue. I flushed my heater core twice and that did the job. I'm almost positive that's what your problem is, seems very common based on my research here.
- Thread starter
- #4
Yup just looked at the maintenance records and it states that there is debris and a clogged heater core. Also noticed some heavy sediment in the radiator. Radiator was replaced in 2022 however. Looks like I need to do a complete coolant flush and a heater core flush.
What was your procedure for flushing the heater core?
All I did was disconnect the hoses at the heater core and fit a garden hose over both ends of the heater core to flush it out both ways. The first time I did it was with water only which temporarily fixed it with lukewarm heat. The second time around I got some Limeaway and used a funnel and hose to get it down the heater core to let it sit for about an hour before flushing it again - that seemed to have fixed it. I used steps similar to Scotty Kilmer on YouTube. Was honestly a PITA for me and I hope to never do it again. I just changed all 4 globes and bled my AHC system yesterday and that job seemed much easier...which could be a good thing depending on how I look at it.
I would try flushing the heater core first before doing the whole coolant unless that'll make you feel better. The previous owner had a new radiator put in my car with new coolant flush less than a year ago but that obviously wasn't enough to flush out the heater core.
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- #7
Will get on that. Is weak airflow also a symptom of a clogged heater core? I notice that on all the settings but high the airflow is very weak
Might have clogged cabin air filters or even more fun, no cabin air filter and a bunch of junk on the evaporator coils bc Toyota didn't see fit to install filters from the factory.
shtbrwn86
SILVER Star
If you are careful you can use a metal pick to kind of pry in there and break the "seal". Just make sure you don't poke a hole in the hose! Alternatively, if your hoses are original you could always just cut through the hoses and replace them. That's what I did but I was also replacing the heater Ts and all hoses back there.
shtbrwn86
SILVER Star
When were the heater Ts last replaced?
- Thread starter
- #12
I’m not sure. They current Ts are definitely not the Oem plastic black Ts, they are rectangular and metal. I assume they were replaced when the PO had the heater core flushed in 2021. I tried using a metal pick but had no success.
If I decide to cut the hose and replace the small hose that goes from the heater core nipple to the heater T, can I use any generic 5/8 heater hose?
Never assume the heater tees were done, ever. Don’t bother inspecting them because some of them will crack if you merely look at them wrong. Just buy two 8724860460 and replace them asap. It’s $20, 60 minute job and you’re good for 90k miles.
I was assured by PO the tees were replaced when the radiator was done. I pulled the tees myself and I’m sure glad I did since one was broke.
For breaking the seal, spray it down with soapy water and keep trying with a pry bar or pick.
w/r to heater core hoses, can the access points be at the t's on the firewall? seems to me that hoses at that point might be easier to remove.....pluse allows cursory inspecton of the t's as a bonus.
Also, i read here on mud about leaving the ac function on 100% of the time along with the "auto" heat function. This seems to work well for cabin comfort. I'm doing that now with my '04.
Also, i read here on mud about leaving the ac function on 100% of the time along with the "auto" heat function. This seems to work well for cabin comfort. I'm doing that now with my '04.
I feel your pain - honestly you just might have to manhandle it and keep pulling on it hard while being careful not to bend/break the metal tubes. Keep on keeping on and it'll come off with some persistence.
- Thread starter
- #17
I've read that some replace them with brass T's? Is there any benefit to that over OEM?
The way its looking I will probably just cut the hoses and replace them along with the T's, just as preventative maintenance.
I don’t like metal tees in the system. Introducing dissimilar metals opens the door for additional corrosion mechanisms of things I care about (like my radiator). I’ll gladly do the OEM at 90k. Changing hoses is a great idea.
Could also be a blower motor getting tired. I just replaced the cabin air filters on my 2000 LX and they were filthy af with debris inside the housing. Minimal difference in airflow but good peace of mind. I had a blower motor go out on a 99 Camaro Z28 which had similar symptoms as you described.
