jayjw

I had the same problem with my 94 LS400 for the past 6 or 7 months. It was so bad that sometimes I felt the engine almost stalled. Everytime when I stoped in front of traffic light or stop signs, I couldn't to watch the engine rpm. Sometimes it was below 200. I did a lot of reserch and study. I believe it was the flawed programming in the ECU. The ECU simply can't handle the situation when the Power Steering Idle Up valve stopped working. Here is what I did. Please read this URL. http://www.clublexus.com/forums/showthread.php?t=239568 After I did that, the low idle speed problem completely gone. It has been two weeks now, the car runs perfectly. The Idle Speed is right at 650 when the car is idling.