Rough idle and hesitation, symptoms of a vacuum leak but seemingly normal fuel trims?

Rough idle and hesitation, symptoms of a vacuum leak but seemingly normal fuel trims? - 1

Added (1). My car has had a very annoying hesitation / performance issue with a rough idle. It feels like bursts of vibrations when stopped (not a motor mount), almost like a vacuum leak. However my fuel trims are around 5-15% total fuel trim.

Added (2). I have no check engine light. I have also noticed sometimes when accelerating from a stop, the car has a very slightly delayed response and kind of jerks, and then accelerates.

Added (3). Today I have been smelling a slight gasoline smell outside of my car after I turn it on. Any ideas? I'm pretty lost. Thanks!

Added (4). (Sorry, Y! A is screwed up and I have to post "Updates" with my info)…

One more thing, it's not a leaky injector (had them all checked and cleaned at a Honda dealer).

Is the car going into closed loop? Replace the PCV valve. Check for O2 sensor/s response by spraying carb cleaner on a vacuum line. Check TPS, MAP and MAF sensor voltage values/waveform as you rev the car. Check for Intake and Engine Coolant Temp sensor values when the engine is cold and warm. Check for a thermostat that is stuck open. Check for a leaking fuel pressure regulator (remove the vacuum line and plug it while the engine is idling and wait for about 10 minutes and check if the regulator leaks. Plug the EGR valve and check. Check for a strong spark and resistances of the coils. Check camshaft and crankshaft position pulse with a labscope. Get a smoke machine and check for vacuum leaks.

Spray brake cleaner or propane around the intake manifold and see if the fuel trims change.

Check fuel lines for leaks, if you smell gas then it's obviously leaking somewhere.

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