I have a 2011 Buick Regal non turbo with two codes

What is your question?

explicated as Fuel Pressure Regulator 1 Exceeded Control Limits - Pressure Too LowIgnition 1 Switch Circuit 2,” and this is logged when the PCM detects a voltage difference between multiple ignition feeds. Code P1682 is often caused by a malfunctioning ignition switch, a bad electrical connection, and an open or shorted ignition switch harness. They where hooking up an inline fuse for the subs in the car and hook stuff up wrong and blew up an amp. The remote wire or memory wire was burnt all the way to the fuse box located next to steering wheel I removed all the wiring they put in. Replaced main relay because it was buzzing and humming and still have issues can get it to run for maybe 15 mins reduced power and engine light comes on acts fine til u get up to speed also the radio was dancing.

What makes this problem better or worse?

When main relay cools down or I take it out and put it in starts up

How long has your 2011 Buick Regal had this problem?

Few weeks