Rav 4 engine flutter

Our 1999 automatic Rav 4 (157,000 mi) occasionally won’t accelerate from a full stop or from a low, in-town speed. You step on the accelerator and the engine just flutters at low rpm, stuttering. If you drop it into neutral and start revving it will eventually “catch” and be fine. Very dangerous when entering roadways. We have a new timing belt, cleaned up throttle plate, new sparks, water pump, oxygen sensor. Any ideas? Thanks!

When–if ever–was the fuel filter replaced?