Fuel system / a/f ratio issue?
 

Looking for someone to shed some light on an issue (possibly multiple issues) that I am having and have been having for a while. I have a fuel pressure gauge installed and it used to run ~60 psi at idle/cruise and ~66 psi under load (i.e. merging onto highway etc...). My pressure sensor developed a leak therefore causing the gauge to misread. After installing a new one it seemed to be running fine but then a couple months ago started reading ~63 psi at idle, ~65 psi cruising and goes all the way to 80psi under load. I checked the sensor for leaks and there doesn't seem to be any in the sensor or the hose. I was having a rough idle and thought it could be a vacuum leak, bad maf, etc... so I had to go back to the drawing board.

Since then I have changed the o2 sensors, spark plugs, MAF and had it smoke tested by a shop and had a tiny leak at a rubber boat which they tightened and sent me on my way. The idle is much more steady, except for when I have the A/C on it seems to want to drop a little at stop lights so I am assuming that is a bad bearing or my compressor failing. As for the weird pressure reading can anyone help point me in the right direction? I replaced fuel filter and fuel pump relay last year but haven't check the fuel pump itself nor have I checked for clogged injectors. Only check engine light I received was P0103 the other day which, after shutting the car off and turning it back on, disappeared and hasn't been seen since. Any help/suggestions/thoughts would be greatly appreciated as it doesn't seem to be running right as far as being sluggish and seems to have poor acceleration, although it might be in my head as the indy and dealership I have been to say that they haven't noticed that... TIA

Year and model of the car please, and what diagnostics system read this code?

I hope you don't have a fuel pressure hose running into the cockpit ? I would verify the pressure reading before going too far looking for a cause.

LOL no way! It is an electronic gauge just wires running into the cockpit. I was thinking about taking it somewhere to have it verified to see if it's the gauge/sensor unit or if it's something else. It's a 2001 base and the system that I posted that from is a iOS obd2 app called Dashcommand.