RDK1990LexusLS400

I have a same type problem and wrote the forum about it also . I had a few responses. Follow the link below or search my posts. I hope this helps. http://us.lexusownersclub.com/forums/index...ndpost&p=132437 ← Thanks for the link. It was very informative and a great help.

Recently I've seen a couple of comments about "1200 RPM Ping" as an engine issue for older LS400s. Its a perfect description of my primary concern with my LS. It only seems to do it between 900 - 1300 RPM when the engine is and/or the weather is hot and/or the engine is under a slight load (short incline, etc.) I know what I think but I'd like to hear what others have experienced. Thanks - this is a great forum for those that love these cars.