Broken Brz :( help
 

Hey guys im new to the forum, i recently purchased a used 2014 brz from someone and the car has stalled on me with check engine light and left me stranded twice in the 3 weeks of owning it. (the previous owner bought the car from a guy in new jersey and it had the supercharger kit installed and a flashtune tablet, the car did not run really good when he had it, he blew the engine on the road trip back and swapped the engine, ecu and map sensor at a local high performance shop)
When i first got the car i practiced driving in it for around 30 miles and it was running perfectly fine and soon after that the check engine light came on and the car stopped working. I was left stranded after, pushed the car w my buddy to the parking lot and left it over night. However i managed to start the car the next day by pressing the throttle when starting the car with the clutch pushed in. The engine cranked about 5 seconds and it started, every since that it will take me at least 5 seconds to cold start the car. The ob2 codes that i have from the first check engine light are "P0068","P0123","P0223". With the codes i had from my ob2 scanner i took the car to the high performance shop where the previous owner took it to and the mechanics tested the TPS sensor according to the codes i provided and this is what they gave me : "Scanned and road tested the vehicle. Felt drivability issues. Monitored TPS sensor percentage while on the road test. TPS sensor responds as it should. Reading 100% at WOT. Scan and found codes u0155 Lost communication with instrument panel cluster control module. P1604 start ability malfunction." After the TPS sensor test the shop told me that they couldnt find any problem and it will take them another month for a second check because the number of cars in the shop, so i drove the car home and it was running no problem, no CEL, nothing at all.
The second CEL happened today, which is when i drove the car to a car wash. I put the car in neutral and ebrake on, the car just stalled for no reason without a check engine light either, so i restarted the car, it was a slow start, didn't sound good at all, the car idled very rough around 800 rpm and soon stalled with a check engine light on. The codes i got today were P0087,P0171. I erased the codes just to see if anything would came back on and i managed to drive the car back home which is around 7 miles, it didn't stall at any red light and after i parked the car i let it idle itself for about 3mins it stalled again. After letting it cool down i restarted the car with rough slow crank and it idled about 5 more mins before it stalled.
Another thing i have noticed is that the mile count on the car isnt correct, i drove today about total of 30 miles and it was adding 47 miles reading on the odometer, i don't know if that has anything to do with the fuel rail failure codes but that's just something i noticed since i got the car.
At this point i don't know what to do with the car i do not want to throw in couple more grand into fixing the car like the previous owner just to have it break on me again, any one with a supercharged brz with similar experience that had a fix for this please help me, any help or suggestions is greatly appreciated!!
The major mods i know so far are : edelbrock eforce supercharger, tomei headers, not sure the brand but it has coilovers and lowering springs, perrin exhaust, pretty sure it's a new FA20 engine with 2000 ish miles on it according to the previous owner who bought the new engine. the tune is done at a professional tuner shop and it was ecutek, i think it made around 300 whp on the dyno.
really any help is appreciated, i have no idea what is going on with the car :(

I'd return it to stock and get it running well. There could be a multitude of issues that the supercharger is introducing. What are you using for tuning?? I'd have gotten receipts for all the work the previous owner had done with mileage and dates.

What are you using to verify your odometer tracking? I'd go on the interstate, find an even mile marker, then drive 50 miles. Set your tripometer to 0 first, and after 50 miles of travel (via mile markers) see what your tripometer reads. I hope you got this car for a steal..

yah i wouldn't say i got it for a steal the previous owner got it for 18k a year ago and put a bunch of fix to it which cost him about couple grand and he send it to me for 19k... the car was running fine when i first got it and the previous shop that swapped the ecu and everything said it was running fine too thats why i would even get this car in the first place, i dont know why it's like this right now :(

What do you mean practiced driving? Is this your first manual? I ask because the codes you gave are all throttle position sensor codes. Any chance you broke something while "practicing"?

What do you mean, swapped? Did they change the tune after you bought it?

i don't think i did, ya it was my first manual lol. they said it had a aftermarket tune tablet like one of those they sell on the ft86 speed factory, and they took that out and put a new ecu in and changed the map sensor, and put a tune on it i didn't have this car when this happened and im pretty sure the new tune is ecutek

the only thing i was concerned first was i was engine braking on downshifts and i might have broke the throttle sensor ? so the first thing i had the shop check when i took it in was the throttle sensor and it was completely fine and the check engine light didn't come on so i just drove home, i drove this car for about at least 50 miles after with no problem until yesterday, i was so confused

Those codes are all throttle position sensor related. Could be as simple as a loose wire. Would also explain the issues after going through the carwash if an exposed clip got damp.
I would start checking the wires and connections before looking for other issues.


Edit: Too slow. So they checked the sensor itself did they check the wires leading to it? If it ran fine after they checked it then went again it could be a loose wire.

the next thing they said they were gonna do is to check wires but it would take them at least another month to do it so i just drove it home hoping nothing could happen... i guess i should be more patient with the car then. I tried to check the sensor connection before, i disconnected the TPS sensor because when i just have the car on without engine on i can hear this whining sound coming from the TPS sensor area and i try disconnecting it and reconnecting it didn't do anything. What should i check for wiring tho, i can go check right now but as far as the wire i can see in the engine bay nothing looks busted i can go out and snap a picture for you i dont even know where i should start checking

That is the fun with wires. They can look perfect on the outside but be broken inside.
It could also be a vacuum leak someplace. Also fun to track down.

should i have the shop check for vacuum leak and loose wire then? right now i can't even tell the shop what's wrong with my car lol, do you think i should upgrade the fuel pump too? the codes about the fuel running too lean is kinda worrying me

The Supercharger adds an element of fun to the vacuum leak possibility.

Yep it sure does. That is why I said to start with the basics. Could also be a tune issue but not to that point yet.
I hated chasing vacuum leaks and broken wires.

but how can the vacuum leak and loose wires explain the slow crank start tho? i understand it's winter right now but it was starting perfectly fine like any normal car before the first break down, now it does this 5 seconds slow crank start everytime i start the car, i read the other posts about that people only deal with it occasionally, i deal it with it every start. i also took the free battery test at the dealership, the reading is crank health rated: 640 CCA, measured: 644CCA, voltage: 12.67V. Even tho it does seem to start quicker with faster crank with a jumper cable to my friends car but the dealership says the battery has more than enough power to start the car