OKIDOG

first off thanks for your help on my idle last time!
My truck overheats in one condition-after a few minutes of highway driving. It is stable otherwise.
Here is what I have done to trouble shoot so far:
pressure test and check OEM radiator for stoppage/blockage
gut thermostat
burp system
all new fluids
stock timing
valve adj
new egr

fan clutch
water pump
oem radiator cap
hoses
no leaks
new 50/50
compression tested
There are no issues with the head gaskets
There is no knocking-it runs fine even when this hot
The 02 tested ok when cold on ohmeter

No exaust leaks between engine and 02 sensor
no trouble codes


Could it be a lean condition making it this hot?
Should I do the AFM mod or replace the 02 sensor?

Any help would be greatly appreciated

willyt4r

If the Ac condensor fan isnt working that could explain your problem. there is a resistor block that falls apart.

TNRabbit

If you're overheating on the highway, I'd guess your radiator is clogged. Has it ever had stop leak or equivalent used in it?

OKIDOG

It runs a bit cooler with the AC off and the heater on, but the needle is still very close to red & if I push it, coolant will boil out into overflow.

OKIDOG

From what I've read,
a bad O2 would make it richer, not leaner
if it was caused by a lean condition, there would be knocking/detonation
so adj the afm probably won't help
Any ideas where to go next?

cracker_1

X2 check your radiator, probably clogged....

james severus

my 2 cents...

my 3vz was doing similar thing. I went through everything, replaced all but radiator. Radiator was flowing fine.

However, I took some advice and replaced the radiator. Not a problem since. I'm not the best mechanic but seemed when hot the flow stopped in the radiator.

OKIDOG

I think I am going to have to try a radiator. If anyone knows of a high performance fan clutch or water pump, please let me know, thanks!

TNRabbit

OEM stock fan clutch & water pump work fine under all conditions.

You may have flow in the radiator, but you're not getting ENOUGH at speed when you're generating a lot of heat. You have clogged passages. I almost guarantee someone has used stop-leak or equivalent in it at some point.

how many miles on the engine? Do you use Toyota RED coolant?

OKIDOG

I'm running green 50/50-I hate to replace that nice OEM brass top radiator. Should I have it cleaned, clean it myself or just replace it? 130Kmiles

cracker_1

Do you have a good radiator shop nearby? They can check to see if there is a problem before you replace/rod it.

pholife

any updates...I have the same problem and looking into getting a new radiator too...thanks

TNRabbit

FYI: https://www.yotatech.com/forums/f116...d-pics-193478/

angrydogtattoo

I have a 22RE and not the 3.0, but I picked up a really nice all aluminum one from an online auction, $125 I think with shipping and not only did it look cool, but it has run very nice and installed like a breeze, I had minimal tweaking to get it in.