How do you remove thermostat on a 1993 Lexus ES300?

Follow the upper rad hose to the engine and there will be a housing there with the thernostat in it. Be sure when reinstalling it the spring goes toward the engine. If you install it backward it will overheat in about 3 minutes. If your engine is overheating, generally the thermostat isn't the problem. It is the cooling fans not operating properly.

The answer above is actually wrong for the 1993 Lexus ES300. You actually follow the lower hose up to the water pump where there is a housing for the thermostat. To remove this you will first, want to take the front right tire off then the dust guard for it; the thermostat housing should now be viseable. Then you will want to take the plastic windshield washer, and engine coolant reserviors off to make the job easier. Next take the bottom rad. hose off the water pump(where it goes to, from the radiator). then struggle for awhile with taking the three nuts that hold the thermostat housing together (a wobbler bit on a socket wrench can make this job easier). Once these are off you can unplug electric plug on top of the housing, pull that part of the housing off and there the thermostat sits in all of its evasive gloriousness waitng for you to rip it from its mother and throw it away.