I have a 97 Legacy GT auto and experience a similar problem to those described. I'm posting this mostly to just "get it out".
Maybe what I have is correctly called "hesitation", but I know exactly when it will happen though I don't understand why it happens. Hopefully my description makes some sense.
What I experience almost always happens after driving on the highway at high speed (60-80MPH) and then slowing down to a near stop at the end of an off ramp. At this point the ECU sometimes keeps the engine idling around 1000 rpm (according to my tach), which is high for my car. Maybe the ECU is in "performance mode"? If I stay at a standstill, the engine will gradually slow down to about 750 rpm, which is the normal idle speed for my car. But, as usually happens at off-ramps with yield signs, I end up slowly moving to the end of the ramp at 3-7 mph or so and never fully stop. During this period, as long as I keep moving, even slowly, when I touch the throttle I feel and see the engine rpm very briefly drop to below 500 rpm. It feels like the engine is about to stall. Then it catches and goes to 1200 rpm or so and I accelerate normally. It feels like a lurch. Letting off the throttle is usually fine, although sometimes I will feel a strange engine/transmission backpressure that gives a decellerating lurch type of feeling. The engine idles at 1000 rpm again and the same process repeats indefinitely throughout the ramp exit process. The only way to stop it is to completely stop the car and wait for the engine rpm to drop to 750, which takes 5-7 seconds.
I find it rather annoying, but I've never actually stalled, nor has it gotten any better or worse over time. It's always been this way since day one of owning the car, which I bought brand new.
- Brian