2006 Is250, 165K.
While driving Check engine light comes on..(blinks occsaionally ) momentary loss of power - so pull off road and rest vehicle for a 15-20 min then all clear for a while then starts again. Spark / Wires issue or carbon build up?

 

Pull the CEL code and post up what it is. We can go from there. Any auto parts store will be able to pull the code for you.