i put new spark plugs fuel pump and fuel filter and still i dont know i was told shock sensor but it has none of the symptoms

 

Welcome to Club Lexus.

Year, miles on car? Any dash lights? Plug it in and see if it reads any trouble codes.
Beyond that, this thread:
https://www.clublexus.com/forums/ls4...es-solved.html

 

mine does the same thing, i'm pretty sure it's one of the cam position sensors or knock sensor going out, if you look at them you'll probably see that the wire to one or both of them has been rubbing on the serpentine belt causing some wire to be exposed.

 

Also check the crank sensor as no output = no spark and they can become intermittent when warm.