P1103 and P0130

Hello everyone! For the past month I've went into a rabbit hole to try and figure out why my car has been running like **** and when I say **** I mean rough idle gas consumption ~1.5-2+l/h on idle when driving and the car is cold it stutters and losses boost and boosts again rapidly. I've fixed a hose that was split open after the n249 (or whatever it's called) and right before the Y split, and the PCV hose after the Y split that connects to the engine. I was hoping that these fixes solved my problem but unfortunately they didn't. These codes still persist. Also almost the same time that these problems started I wired an amplifier and the positive wire I fished it though the gormet below the steering wheel (could I have damaged any wires there?). And before all these, about 2 months ago, when my car was cold when I was driving and I pressed the clutch the rpms would drop like crazy and sometimes it would turn off, and this happened until the car warmed up. But I blamed the clutch switch in front of the pedal that was faulty, could that be the start of the O2 failure;

I'm sorry for the long paragraph, but I can't seem to figure out the problem and it's driving me crazy and neither a mechanic wants to spend time to search the cause.

Some info about the 02 sensor:

When it's on idle the voltage that it reads is 0.020 volts and sometimes it jumps to normal volts, when the car is turned off it reads ~1.5 volts. The heater S1 was turning off and on rapidly on idle. And when I tried to test the sensor it said test off and after a while it that it failed, without giving me the option to test it myself manually

Edited 12 minutes ago12 min by NikoX14