My 1992 es300 seems to be gutless. it starts and runs fine and it even passed emissions, but it seems to have less power than my 4 cylinder honda. Is this typical for a late model lexus. I put a timing light on it and it jumps around from about 12 to past 15 degrees at idle. checked my timing belt, its correct. I have just replaced every vacuum line and hose on the manifold along with new cap, rotor, plugs, ect. any help?