Dark-Hax

So I have a problem with my Cruze 2012 that I'm trying to fix but I need to be get Educated first by asking here to people with experience,

1- When I accelrate at certain speed points it get stuck at that speed and the car feels like it being pushed back and resisting speeding up.
-I noticed from that turning the car off and on fixes the issue sometimes but it goes smoothley that untill I turn it off.

2- Sometimes when I turn on the car even before turning the Engine it gives me Code 84 or sometimes when I'm driving.
- Again solved by Turnning the car off then on but sometimes it presist even after turning the car off and on however it eventually goes away.

3- Car sometimes it works othertimes it doesn't.

4- One time when I was driving I turned off the lights and the engine shut down for some reason had to stop by the side to turn it on agains but it gave code 84.

So what causing all of this? I asked multiple people and they gave me different answers some told me it's the ECU going crazy, some told wiring and electrcity is the problem.

So I have no idea, is it:

Engine
ECU
Electrcity


I would appreciate a good Answer in this matter.

tech2

Code 84 is not a generic code and does not display what module the fault set it. Have someone with a scan tool read out all the codes in all the modules. A full function scan tool is required. a code reader only reads powertrain codes.

this is the starting point to any diagnosis.