Tp sensor, sticky iac, fuel pressure, sooooooooooo many little things that can add up to your concern.
If you have a manual, (or get the info online), ck what the tp reads @ idle. Also, simple enough to clean the iac, (don't recommend it myself, just replace them), in either case, also ck fuel pressure.
Still sounds like bad tp sensor, tho.
Good luck. Have fun.

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