Kill my subie or invest in it???

[stivirgin]

Hello knowledgeable subie falk.

As my user name implies, im very new to subies and even newer to turbos.
Iv got a list of concerns and questions regarding my car and id like see if anyone could offer some assistance (please).

Iv had my car for 18 months after two-timing my much loved R-34 skyline. Since iv had the Impreza, the engine MIL light has been on constant and after performing a diagnostic test using the green and black plugs it turned out to be the knock sensor and throttle sensor. Ivestaging the the knock sensor condition lead me to discover that the wiring on the harness side had been damaged causeing the connector to harness to be ripped of. I suspect the damage occurred during the previous owners engine swap (an 00 in a 99 chassis). Since i dont like spending money for something that i could attempt myself, i decided to get some electrical tape and rewire the ks to harness. I left battery disconnected for a day and then check the diagnostics code again...to my surprise the knock sensor code has vanished wen iv got green connecters together.. But with the black pair the ks code stil appears... Now i understand that the blak pair are supose to be any recent codes in the ecu memory.so should i not worry about the code still being prescent and consider one of my faults dead since it no longer shows with green pair connected?? I must add with those green pair connected that the car does wot i supose its meant to....fans start wurring and relays clicking like a test mode kinda. With the second fault (throttle sensor) i managed to remove the code once after i noticed the ts is adjustable but because im a perfectionist, i didnt like the way my car idled so i readjusted it and now i cant get fault to go away again. Is there some guideline to adjust the throttle sensor? I noticed that the voltages change with each adjustment so there must be a knack to positioning it?? Either that or the sensor may hav seen its last days. Iv changed my mind about including my other car issues in this post as iv already given u guys a novel to read... Any advice would be greatly appreciated