P0301 1998 toyota avalon

Question

have changed plugs wires and coils also replaced fuel injector

Answer 1

HI there,

With all that you have done to eliminate the code, the only thing left is an internal issue. I would do a compression test and if the compression is good, follow it up with a leak down test. The leak down test will tell you if you have any carbon build up on the valves that may be causing the misfire.