Honda Civic High RPM and Gas Smell Problem

Hey everyone! Ive got a few questions about my Honda Civic 2002 Pakistani version, and Im hoping someone can help me resolve this issue. I believe our discussion might benefit others too. So, heres the problem:

Recently, I filled the gas for the AC and its compressor connection wires, and since then, my car has been acting weird. Whenever I press the clutch and release the accelerator while driving, the RPM shoots up to 1500-2000 and stays there for about 15 seconds. After that, it gradually s when I release the clutch pedal. This happens whether the AC is on o r off. Also, Ive noticed a misfire that I can feel from the silencer.

I tried disconnecting the AC from the Fuse Box, but the problem remains the same. To fix it, Ive already replaced the IACV and cleaned and serviced the Throttle body, MAF, injectors, and spark plugs which had carbon buildup. The misfire issue has improved somewhat, but Im still facing the following problems:

High RPM when the clutch is released Ive checked, and the accelerator wire isnt stuck. However, its a random problem that doesnt happen every time.
RPM stays high for about 10 seconds even when I press and release the accelerator while the car is parked.
I notice a gasoline smell o r the feeling of unburned fuel when the car is idling.
Im thinking of checking the fuel filter, which I believe is located somewhere under the tank outside the vehicle. The car used to be silent, but now it has a bit louder sound, like its running rich. By the way, I regularly use Havoline 20-50 oil and service the car on time.

Ive already checked for vacuum leaks and made sure all the pipes are okay. Ive also checked the coils, and everything seems fine. I even tried different fuel pumps, but the problem persists.

If anyone has any suggestions o r ideas, Id really appreciate your help. Thank you!