What is causing car to stall when going into drive or reverse, or while in park after pumping accelerator?

When the car is warmed up and running in park, it idles fine, but as soon as you quickly pump (or tap) the accelerator, and quickly release, it stalls out. But if you press down on the accelerator normally, it doesn't stall (mostly).

While the car is idling/stopped in drive or reverse it also stalls, but not when it is in neutral.

I read a suggestion on here similar to my issue, and the suggestion stated that it was most likely the torque converter, but I have a couple questions, if this is most likely the case:

1. Why would the torque converter cause the engine to stall while in park after pumping the accelerator? Does it affect the engine even when in park?

2. I was told that the transmission fluid and filter haven't been changed in many years. Could it be possible that it's not the torque converter, but the filter (and fluid) needs changing?


Note: I cleaned the throttle body, replaced the air filter, and installed new spark plugs, and wires. I suspect the problem is either the fuel pump/filter, torque converter, or dirty fuel injectors.

I'm going to look at the air intake hose for cracks. I never bothered to inspect it. Maybe that's the problem.

Thanks in advance for any comments.