The accelerator is connected to the throttle bellcrank via a regular, old cable (mechanical). On the underside of the throttle body is the TPS. The TPS reports the throttle position to the PCM and the PCM uses it for fuel, spark advance, shift points, and other purposes.
https://www.youtube.com/watch?v=G83vmQijMg4
The stalling, hesitation, and faltering on acceleration could be due to many causes. Are there any trouble codes, or is the MIL on alerting you of a problem/code?