I put a new radiator in my 07 tonight and did all the steps to burb the system; used bleeding funnel system, raised front end up, put heat on high with fan on low and let vehicle get to operating temp. I don’t know if my thermostat opened up. The radiator never got warm nor did the lower radiator hose that goes to the thermostat, however the vehicle temp gauge never went above where it normally does and it blew out good heat. How can I tell if my thermostat is opening up? This vehicle doesn’t have a bleeder valve/screw does it? Thanks, Scott

 

Did you drive it? I'm not sure how cold it is there, but it might take a while to get hot enough just idling. Plus the jostling helps move things along. It sounds like you've done as much as you can on jackstands.

 

I took it for a 30 min drive this morning at 60mph and the temp gauge stayed perfect. I checked the radiator and lower hose when I got home and both were still cold. I can’t imagine the thermostat isn’t opening up if it didn’t overheat on my drive but can’t explain why radiator and hose were still cold if it did open. Not sure if I should just leave it as it is since it seems fine or replace the thermostat.

 

The gauge is lying to you. Unless the temp gets very hot, the pointer will always stay in the middle of the range, so that the Average Joe doesn't freak out.
Try a ODB dongle - most of them will report the temperature reading off the sensor.

Chip H.

 

I took the Lexus for a drive with the OBD plugged in. The car ran at a constant 194 degrees on a level road. I took it up a mile long hill to see what it would peak at and it hit 201 degrees, when I got back on level road it went back to 194 degrees. Is that good?

 

Ya, that's within normal expected temps. Did you pull over at the top of the hill and see if the lower rad hose had any heat in it? Or the rad?

 

I didn’t check rad or lower hose but I will next time I drive it. I would think if the thermostat didn’t open, the temp would have sky rocketed.

 

How can I tell if my thermostat is opening up?

You can check the thermostat is opening up by setting your heater temperature to maximum level. If the vents blow very hot air, that when the thermostat open up and the water in the system circulates.