I recently took off my throttle body to clean it, I put in new PCV and vacuum hoses as well. Now I idle at around 500rpm when the car is warmed up. Any ideas?

 

Before this my idle was around 800rpm, there also was a bit of coolant in the bottom on the intake manifold but I cleaned it out if that matters.

 

A new throttle body needs to reset the ECU. A simple way to reset is to remove the battery terminal for several minutes or more. Other than this, it's better to clean the air mix passages using a compressor + a can of carbon solvent.

 

Okay I will clean out the idle bypass valve again maybe it was the gasket I put on it, I already disconnected the battery for a while but I did it while the throttle was detached so I will do that again as well, thank you!

 

You need to clean out the two larger ports as well as the 8 little holes when you remove the little metal cover on top of the throttle body - as Yamae states. There are other posts and illustration on this especially in the LS400 forum.

 

yeah I cleaned the two larger ports as well