Both - a failing fuel pump will lose pressure, and the engine will run as though it is starving for gas.
Checking the fuel pressure checked and getting lower pressure readings than normal will indicate the need for a new pump.
No the reserve fuel is to just let you know you are in need of fuel and to give you time to get it with out running out of fuel.
it lasts 120 days just like your blood
The first step is to find out just what is causing your eye sight to deteriorate.
Just open gas cap to unpressurize the system. Disconnect the fuel line from the fuel rail. Just disconnect the harness on each one then unbolt the rail and remove them. You might need a tool for disconnecting the fuel line from the fuel rail. You didnt specify what vehicle this is that is all the info I can give. Hope this helps.
Check for fuel pressure to insure that the new pump operates properly. Make sure that the fuel filter was not installed backwards. The filter has an arrow to indicate fuel flow direction.
All smell are just molecules. The gradually desperse into small particles that your nose adjusts or you just can smell it anymore.
fuel filter is under the car, just in front of driver's rear wheel right next to the fuel tank
That is the correct spelling of "gradually" (a little at a time).
The fuel filter never goes out it just gets clogged acting restricted or lack of power. When the fuel pump goes out it wont start usually it will give you a chance to beat on the tank with a rubber mallet to jolt it and if it starts then it the fuel pump.
In my opinion I would do it gradually so your system can gradually adjust.
No. Just the opposite.
It could be the radiator, hoses, fuel pump or an engine gasket. All of those components just "give out" with time.