same as a Toyota, same as any car
go to your public library and look up the step by step instructions from the manual there
dexron 3
To remove the radio from the 1990 Lexus ES250, first pry the face plate from the dashboard. Then remove the clips that hold each side of the radio. Then, remove the wires to release the radio.
on the exhaust
Call OnStar
it is located in the fuel tank
got to this website to find out http://www.md-cars.com/uploads/content/company_Toyota/ES250.jpg
== It's the medium sized black box located under the drivers seat...
you should be able to find a shop manual at the local library with the right information on this -- make copies of the pages, as they are usually for REFERENCE only...:)
Remove the retaining ring from the top of your 1990 Lexus ignition switch. The ignition switch will slide out. Remove the wiring harness.
In order to remove the headliner, your have to remove the seats or it will not fit out of the car.
replace upper radiator hose and install a new thermostat. see what happens. or turn it on without the thermostat for a while and see if it still overheats.
Remove the transmission oil pan