Swiss cheese air system... several questions.

[bgugi]

My car recently developed symptoms of what i believe to be a fairly severe, though intermittent, vacuum leak.

current codes:
p0135 and p0141 - o2 1&2 heater faults
p1104 wastegate solenoid

Symptoms:
First ~minute of driving is fairly typical, easy transition into/out of boost, fairly normal power, etc. afterwards, car seems to be fairly bipolar. sometimes i can press down on the petal and receive virtually no power, 2-3lbs of boost, and a loud well... fart noise (high exhaust pressure/temp?), but if the manifold can get above about 4lbs, the car seems to run great, good power, normal exhaust note, etc. boost peaks at around 13-15lbs then backs down to around 12. Idle is sporadic, between 1500rpm:20inhg steady and 600rpm:12inhg bouncing, with the lower idle appearing to correspond to "bad" launch.

Known problems:
boost leak test shows leaks:
tb shaft seals
biss screw
#1 fuel injector
iac has 2 dead coils

Now a few questions:
does the o2 heater only assist the sensor reaching temp, or is it necessary to maintain temp (in 12-30 degree(f) weather)?
can incorrect o2 temp lead to bad fuel trim (open loop vs. closed loop problems?)
I'm considering this fiav disable, but I have to pass emissions. I just want to make sure that an FIAV disable won't show any trouble codes (actual emissions don't even matter in my area, just need to pass computer test)

parts:
i already have an iac in the mail.
I'm currently considering this set for my throttle body.
I'm not sure what i need to seal the injectors. only #1 seems to be leaking, but i'm going to do all four since i'm in there (unless i need something absurdly expensive that i'm not seeing) here are some kits... but i'm not really sure which seals are which, and which i'll need/want.

any help is greatly appreciated.

edit: is this considered a valid option?

 

[Dsmkauai]

Lol I was born in Zion and lived in Winthrop harbor for many years bro!!
Dude if you know you have boost leaks and that many, fix them asap. Then move on to other things you will never get things running smooth with multiple boost leaks. Please buy your parts off the vendors on this site! eBay and dsm's don't play well together! Get these for your injectors and you'll be set, you need 4 orings, 4 insulators, and 4 sheets (not nessasary but might as well do it all at once)
STM: 90-99 DSM | OEM MITSUBISHI PARTS | FUEL SYSTEM COMPONENTS
Or just call STM and tell them you need a full set of orings for your injectors stock 450's Most likely the injector insulator is what's leaking
As far as your 2 o2 sensor codes either your wiring is shot or the o2 sensors are shot or even worse the ecu is messed up.
For the other code Check to see if the wg solenoid is even hooked up if it is than just bypass it and run the vac line from your wg to comp cover.

 

[bgugi]

News: the car runs in closed-loop-fault mode, and only seems to be having problems in closed loop. A good stab at the throttle will put it in open loop, and it runs fine.

I am having trouble with the front o2 electrical connector. The damned thing refuses to budge, despite any amount of squeezing pulling prying or otherwise dicking around with the plug. Who seriously thought it was a good idea to bolt the damned thing in place?

 

[McDizle]

Definitely need to get the boost leaks solved first before trouble shooting anything else! They can cause a lot of odd problems