2k hyundai, runs fine thin quits, wait then runs fine again. shows code p1123 expect fuel pump or filter.

What is the code? could be crankshaft sensor.

Wow do You have a bunch of different Sensor and Circuit Problems

0110 Intake Air Temp Circ Malfunction
0121 Throttle Position sensor A Range Problem
0180 Fuel Temperature Sensor A Circuit Malfunction
0335 Crankshaft Pos Sens A Circ Malfunc
1120 Throttl Pos Sensor Circuit
1123 Throt Pos sens Higher then Expected
1127 Exhaust Not Warm Downstream 02 Temp Sensor
1131 Lack of Sig H02S Sens Indicates Running too Lean
Learn more about codes here http://www.troublecodes.net/OBD2/Pcodes/

I would guess with all this You may Have a Connection Problem or a Computer Issue Get the codes reset and monitor as soon as check engine light comes on to see what codes com up first and what codes are pending
Good Luck Rickie

If you need further help, reach me via phone at https://www.6ya.com/expert/richard_b70d968cd1a1d293

LONG TERM FUEL TRIM FUEL MIXTURE TOO RICH, POSSIBLE CAUSES FAULTY OXYGEN SENSOR, FAULTY FUEL PRESSURE REGULATOR,DIRTY FUEL INJECTORS STICK OPEN,OR ENGINE HAS MECHANICAL FAILURE FAULTY CYLINDER COULD HAVE LEAKING VALVE OR VALVES COULD HAVE INTAKE LEAK.

clogged catalytic converter, replace.

chek filters for fuel on frame and in tank

reset the alarn/immobiliser.........

try turning key swicth on and off several times if you replaced fuel filter it may have to reprime its self turn key on let pump run turn off turn on again do it 4 or 5 times might help

Does the fuel line still have 55 PSI when engine warmed up? Any other codes show up?

This problem of misfire in the damp is commonly caused by faulty HT leads or electronic coils. Check all plug leads first.

P1123 fault code is often associated with a faulty MAF on Hyundai cars. However first start at the air inlet tube, checking for obstructions or leaking vacuum hose which may also cause this code to show.

obdII P1123 is a error refer to Air/fuel controller
OBDII P1123 Fuel Trim Additive, System Too Rich


the obdII P1123 is a error refer to Air/fuel controller


OBDII P1123 Fuel Trim Additive, System Too Rich

the following info is a copy/paste of HMA service:


PRIMARY COMPONENT:

Air/Fuel Control System

SECONDARY SENSOR(S):

Mass Air Flow (MAF) Sensor
Throttle Position (TP) Sensor
Intake Air Temperature (IAT) Sensor
Engine Coolant Temperature (ECT) Sensor
Oxygen Sensors

FAILURE CONDITIONS

If the air/fuel mixture at idle is too rich for more than 30 seconds during two back-to-back trips, this code will be set and the Malfunction Indicator Light (MIL) will be turned on.

Details:


The code will be triggered if the following conditions are met:

Long term fuel trim value (additive) is less than -0.75 ms (-15% to -20%) for 30 seconds or more
Engine speed is less than 880 RPM (1000 RPM, 2.0L Tiburon)
Mass air flow rate is less than 6.1 g/s (7.5 g/s, 2.0L Tiburon)
Engine coolant temperature is greater than 158°F (70°C) [176°F (80°C), Accent]
Engine in closed loop operation
No canister purge occurring