Hey I think I am having the same problem with my 2000 RX300 :( Let me know if you get any helpful replies... Thanks!
I have a 2000 RX300 also. I don't have a problem starting at all. What happens with me is that when idling at a light or whereever, the RPMs drop by 100RPM or more and makes it feel a little rough. If I shift to neutral or park, the RPMs go back up.
While under warranty, I brought it to the dealer but they didn't find a solution even though they tried a few things. The Dayton Lexus guys have been great, no complaints, but would love to fix this idle thing.
Did you try the suggested fix above and did it fix your problem?
thanks
