Shkspier

I had almost the identical problem the day after I bought my 2000 RX300. Like you, I had driven her hard and found no problems. Not 12 hours after signing the contract, the daggone check engine light came on! I did a little research and learned that for some reason, this light also comes on when you're out of fuel . Now, here's my theory (feel free to dispell it) --> I had been <1/4 tank and made a short stop. I suspect that the low fuel sensor in the tank was momentarily uncovered thereby setting off the check engine light. I refueled and after about 3 or 4 trips, the light magically disappeared. Imagine my relief! :) No new problems to report. This vehicle drives like a dream!

Thanks for the reponse Jon. I will research the transmission problems (though mine currently seems to be smooth). What type of synthetic oil do you use/recommend? What filter? I usually change my own oil -- is it pretty straight-forward in the RX300?

In response to JLCOP's recommendation on new oil . . . I also am a new "used" Lexus owner. Just bought a 2000 RX300 with ~44,500 miles for about $26K. I did not go with the extended warranty relying instead on the remainder of my factory powertrain warranty (and considering that it's a Lexus). That being said, I've been told that synthetic oil is the way to go. However, how do I know if my engine has been using conventional or synthetic to date? Does it matter? If it's been using conventional and I replace with synthetic, can I damage the engine? Is it true that you can go longer between oil changes with synthetic? Thanks for the advice. It's good to know that this forum is here to help out!