Check engine light is on codes p1031 a/f sensor heater & code p1148 a/f close loop. Bank 1. I want to know what parts I need to get it fix.

Replace the power steering pressure sensor. replace both the O2 sensors.

code p 1031 refers to heated oxygen sensor(HO2S) bank 1--heater --voltage low===causes --wiring---HO2S
code p 1148 refers to closed loop control--bank 1- inoperative === causes ---wiring---HO2S--- ECM
I am think that you haven't connected the harness up properly
or damaged the wires to the HO2S when disconnecting the harness

Clean out you idle air bypass valve with carb cleaner. P0031 air/fuel sensor 1 heater (B1)bank 1, p0603 engine control back up circuit,p1148 closed loop B1. Broken heater in upper O2 sensor is one if not all of your problems. Replace all of your O2 sensors & reset engine light.

Definition of Diagnostic Trouble Code P1148 Audi: Oxygen Control (Bank 2) System too rich Ford: Closed Loop Control Malfunction Infiniti: Closed Loop (Bank 1) Land Rover: Lambda trim post-catalyst bank 1.Short circuit to ground Lincoln: Closed Loop Control Malfunction Mazda: Generator 2 Control Circuit Mercedes: IAT Sensor Circuit Malfunction, Bank 2 Mercury: Closed Loop Control Malfunction Nissan: Closed Loop Volkswagen: Oxygen Control (Bank 2) System too rich

code p1148 refers to closed loop control-bank 1-inoperative===causes--wiring--HO2S front--ECM

Check the wiring is in good condition, replace the HO2S sensor.

loosen and re tighten the top left (rear) o2 sensor and check the connector is not loose...

Wow, looks like I have answered a question like this back on July 26th.
Code 1148 and 1031 are both for the O2 sensor in front of the catalytic converter. The sensor would need to be tested with a scanner and a multi-meter.

Well looks like all 4 codes point to the O2 sensor bank one sensor one.
Code 1148 and 1279 are for problems with the performance of the sensor, code 1031 is for a problem with the heater in the sensor, and code 420 is for poor performance of the catalytic converter on bank one which could also be the sensor.
I would probably replace the sensor or switch it with the one on bank two and see if the codes change.

P1148 - Closed Loop Control Function Bank 1
This mean that the closed loop control function for bank 1 does not operate even when vehicle is driving in the specified condition.

The Powertrain Control Module (PCM) or Electronic Control Module(ECM) monitor the function of the Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor by comparing the signal with the Rear O2 sensor.

Symptoms:
- Engine Light ON (or Service Engine Soon Warning Light)

Possible causes:
- Harness or connectors Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor 1 circuit is open or shorted.
- Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor bank 1
- Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor bank 1 heater

Possible solution:
- Repair harness or connector. If repair is needed
- Replaced Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor bank 1


Then, possible causes are faulty harness or connectors to the air fuel ratio sensor, a faulty air fuel ratio sensor (1) or faulty air fuel ratio sensor (1) heater. Most likely yes it is just faulty sensor. Just replace this devices and reset the stored codes.

Keep us updated.

there is a emission system recall for these codes for your year and model contact the Nissan dealer, it is a no charge repair.
here is the summary of that recall

MALFUNCTION INDICATOR LAMP ON WITH DIAGNOSTIC TROUBLE CODE P0300-P0306, P1273 OR P1283. *TT *SC
Make : NISSAN Model : QUEST Year : 2004
Manufacturer : NISSAN NORTH AMERICA, INC.
Service Bulletin Number : 04028A Date of Bulletin : MAR 24, 2004
NHTSA Item Number : 10005976
Component : ELECTRICAL SYSTEM
Summary :
MALFUNCTION INDICATOR LAMP ON WITH DIAGNOSTIC TROUBLE CODE P1031, P1051, P1148, P1168 (A/F SENSOR HEATER / CLOSED LOOP) ON 5 SPEED AUTOMATIC TRANSMISSIONS ONLY. (THIS VERSION SUPERSEDES NTB04-028.) *TT