The fault codes can be found by searching. There are two possible main causes:
1 a wiring fault. Suggest you check the throttle body connections for corrosion as a start point and check voltages with ignition on while depressing the throttle to see any variation
2 If above seems ok then it is possibly a fault with the throttle body sensors and likely a replacement throttle body is required. In this case second hand ones are the cheapest way forward. If replacing then it needs to be coded to the car.
If you do not have or cannot get use of a diagnostic tool and have the skills then get the garage to sort it.
