CleanCL

OK, I have been having the nightmare of all overheating problems. Car is fine at idle, driving, and stop and go traffic w/ the A/C OFF. Once the A/C goes ON, the car overheats. The fan DOES spin but we can stick our hand in there and stop it regardless of the conditions.

Replaced:
Water pump, radiator, radiator hoses, thermostat, overflow tank, overflow sensor, fan assembly.

Not replaced:
Fan pump, solenoid, AC Pressure Switch, Coolant Temp Sensor, A/C ECU, Cooling path for ATF Oil

We pulled the solenoid out of the car, we put 12V to it, and nothing happened. We used a grinder to take off the little thing inside hoping it would just push oil through at 100%, nothing happened.

Fan pump not working a possibility? Who has replaced it? $300 item from lexus and does not look like a fun job.

mitsuguy

iTrader: (2)

I highly doubt that pump would die - it's built the same way an oil pump is and they are extremely reliable - they almost NEVER wear out, I honestly don't know if I've ever seen one worn so much they wouldn't work (they usually leak first)...

anyways, go to this link: https://www.clublexus.com/forums/sho...d.php?t=288108

and do that - it's a mod too

CleanCL

i don't want to do the electric fans, the stock fan is supposed to be more powerful.

what else could it be then if not the pump?

mitsuguy

iTrader: (2)

I would need to look at the schematics for it - tomorrow I should have a chance to...

CleanCL

i pulled the hoses off the fan assembly to see how the fluid movement was, it was steady stream but not super powerful, so i think that eliminates any possible blockage in the cooling system.

the only thing left is the pump and solenoid because regardless of the other sensors (a/c pressure sensor, coolant temp sensor, a/c ecu), the fan should default into fail safe if anything is wrong, or so the service manual makes it seem.

mitsuguy

iTrader: (2)

um, I just checked mine, and it moves pretty slow too... slow enough to stop with my hand... my car doesn't get hot at all (and it's been 105-110 here for the past two weeks)... maybe you are chasing the wrong problem...

CleanCL

hm, this is just puzzling, the car does not overheat at all, and it's been 80s/90s here, it only overheats when the A/C is on.

i'm going to try the solenoid and the coolant temperature sensor (not sure why this would be the reason since the car does not overheat at all while the a/c is off)

CleanCL

so now the A/C does not blow cold at all. when it did, it overheated. brought it to a shop, they said all they see is some condensation on the evaporator. keep in mind the system was recharged less than 2 months ago. now i'm totally lost, car is just a huge mystery.