what could be the reason why the rpm gauge on my 2003 honda civic is not working? There is a faint smell of gasoline in my car when it is not running. Does this have anything to do with that gauge not working?

 

You can run a test on the RPM gauge by testing the whole dash cluster. it will cause every needle - speedo, temp, fuel, tach, to read across it's full range (to max). If your tachometer (RPM gauge) responds to this, it's going to be a problem with something else. Bad wiring? Blown fuse? etc.

This is a copy/paste from another Honda owner's forum.
1. Push and hold the trip/reset button.
2. Turn the lighting switch ON.
3. Turn the ignition switch ON. (don't start)
4. Within 5 seconds, turn the light switch OFF, then ON, then Off again.
5. Within 5 seconds, release the trip/reset button, then push and release 4 times more.

Takes a try or 2 to get it. The odometer has to be in mileage mode, NOT trip mode when you do this. All the needles will sweep back and forth once. To exit, turn off the ignition. Just push the trip button again to see the needles sweep again while in test mode