High Idle On Start Ls400

[sizbob]

My 1995 LS400 has high idle on start ( about 1800). Then normal after long warm up. Any help?

Also,my post from a while ago ( My mistake on year):

[landar]

Could be your thermostat sticking open. Or a bad temperature sensor. How long does it take for the engine to warm to "normal" temperature? (also please specify your ambient temperature as well because that factors into the warmup time).

Man, thats low miles(100k) for a 95. Have you, or past owner, changed the original timing belt?

[VBdenny]

pretty normal for a long period of high idle. I think normal is around 1600RPM's which gradually decreases to 600. I wouldn't consider it an issue but I understand your concern as I had the same one when I got my LS400 ten years ago.