Check Engine light after: Major service (Fuel pump, ECM, and 7500 miles oil change)

[R2RO]

Hello everyone, i recently have had a problem arise in my FRS.
On the 28th of January my car went in for its:
-7500 mile oil change
-Fuel pump replacement
-ECM Update
When i took it in it had less then between 1/2 through 1/4 of gas left in the tank. When i came back to pick up my car after it was finished with the service. I told my service man why the car was at 1/2 when it was more empty then that when i took it in the morning, he didn't know well rather then question it since i got free gas( Which is really strange and shady) i begun to drive my car back home about 55 miles away. My car stopped on me & the check engine light came on when i was on the freeway and i was really confused since it had 1/4 left in the tank(This is when i really started to get mad) i was wondering what was wrong with this car?
I just took it in for a major service so i was maybe the new fuel pump that they replaced my cricket noise one is faulty too? Well i popped the hood checked all the fuses everything was fine so i called my sister to bring me some gas and a tow truck. Well i put the gas in the tank and Wa-La it started but the check engine light was still on and it started to jerk a lot at low speeds(I don't know why, the gas was Premium 91 What it runs on in California). I drove it to my nearest Toyota Dealer toward the night and dropped the keys off, they called me in the morning and they gave me a brief explanation of what they got when they ran the my car though their system. They said multiple sensors in the car were sending error codes to the ECU, some of them were if i can remember:
-Gasoline level sensor
-Key hole sensor (Said a not original key was placed in the ignition?)
-Fuel pump
-One of the ECUs i think it was the ECM but not sure
-And some more that i can't remember.
Well i should have a full list once they call me on monday about what needs to be replaced on my FR-S, Have you guys had something similar happen when you sent your FR-S in for the Fuel Pump and ECM update?
Just somethings about the car, in December it was in a accident (Hit from the back and sandwiched between two cars No FRAME DAMAGE) and its a Automatic if that is of any information.

[Lonewolf]

Take it back to back to the same dealer, take careful note of your mileage, and push for loaner car until they can get your car squared away.

[BRZnut]

last time someone post that their car broke down after the fuel pump replacment the car burst into flames. Did you smell any gasoline??

[R2RO]

Nothing like that, but thats crazy its at the dealer at the moment. They are trying to find everything that needs to be replaced