It seems to be a very spontaneous and SLOW progressive issue of my RPMs dropping at idle (start ups and stops). Not 100 % sure if its the fuel pump. It occurs maybe 1 or 2 times a week. But my main question here is if I check my fuel pressure will the gauge tell me the fuel pump is bad even if the vehicle is running fine at the time of test?

 

I'd be looking at the IAC and the EGR before I spent too much time with the fuel pump.

An intermittent problem might not show up. Fuel pump problems tend to not be intermittent, but anything is possible. There is also the issue that pressure can be acceptable at low engine output even when volume is way too low at high engine output. In other words, a pressure test is not a volume test. Be sure to test pressure both at idle, and if that's acceptable, also at highway speed--full throttle.

Keep in mind that an electric fuel pump is both a pump and an electric motor, and a fault on either part will cause problems--but the diagnosis and repair is radically different. Low pressure or low volume can be an electrical problem or a pump problem.