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Home/DTC Codes/Ford/F-150/2004-2008 4.2L V6/P1121
P1121

TP Sensor Inconsistent with MAF Sensor

2004-2008 Ford F-150 4.2L V6

Moderate SeverityPowertrain

Description

The Throttle Position sensor and Mass Air Flow sensor readings do not agree with each other. When the throttle shows a certain opening, the MAF does not confirm the expected airflow, indicating one sensor may be faulty.

Symptoms

  • Check Engine Light
  • Poor acceleration
  • Rough idle
  • Hesitation
  • Poor fuel economy

Common Causes

  • Dirty or faulty MAF sensor
  • Faulty TP sensor
  • Vacuum leak
  • Restricted air filter
  • Intake air leak

Diagnostic Steps

  1. Compare TP and MAF readings simultaneously on scan tool
  2. Clean MAF sensor
  3. Check for vacuum leaks
  4. Test TP sensor through full range
  5. Replace air filter if dirty

Repair Notes

Clean MAF sensor. Check for vacuum leaks. Replace faulty sensor.

Related Codes

P0121Throttle/Pedal Position Sensor/Switch A Circuit Range/PerformanceP1101MAF Sensor Out of Self-Test RangeP1101MAF Sensor Out of Self-Test RangeP1101Intake Airflow System PerformanceP1101MAF Sensor Out of Self-Test RangeP1101Intake Airflow System PerformanceP1101Intake Airflow System PerformanceP1101Intake Airflow System PerformanceP1101Intake Airflow System PerformanceP1101Intake Airflow System PerformanceP1101Intake Airflow System PerformanceP1101Intake Airflow System PerformanceP1101Neutral Position Switch Circuit MalfunctionP1101MAF Sensor Out of Self-Test RangeP1120Throttle Position Sensor 1 CircuitP1120Throttle Position Sensor Out of Range LowP1120Throttle Position Sensor 1 CircuitP1120Secondary Throttle Position Sensor CircuitP1120Throttle Position Sensor 1 CircuitP1120Throttle Position Sensor Out of Range LowP1120Throttle Position Sensor 1 CircuitP1120Throttle Position Sensor Out of Range LowP1120Throttle Position Sensor 1 CircuitP1120Throttle Position Sensor Out of Range LowP1120Accelerator Pedal Position Sensor CircuitP1120Throttle Position Sensor 1 CircuitP1120Accelerator Pedal Position Sensor CircuitP1120Throttle Position Sensor 1 CircuitP1120Secondary Throttle Position Sensor CircuitP1120Throttle Position Sensor 1 CircuitP1120Accelerator Pedal Position Sensor Circuit

Other Powertrain Codes

P1121 on Other Vehicles

Ford Aerostar

1990-1997 3.0L V6

Ford Aerostar

1990-1997 4.0L V6

Ford Bronco

1990-1996 4.9L I6 300

Ford Bronco

1990-1996 5.0L V8 302 Windsor

Ford Bronco

1990-1996 5.8L V8 351 Windsor

Ford Bronco

2021-2024 2.3L I4 EcoBoost

Ford Bronco

2021-2024 2.7L V6 EcoBoost

Ford Bronco Raptor

2022-2024 3.0L V6 EcoBoost

Common Questions

What does code P1121 mean on a 2004-2008 Ford F-150?

P1121 stands for "TP Sensor Inconsistent with MAF Sensor". The Throttle Position sensor and Mass Air Flow sensor readings do not agree with each other. When the throttle shows a certain opening, the MAF does not confirm the expected airflow, indicating one sensor may be faulty.

What are the symptoms of P1121 on a Ford F-150?

Common symptoms of P1121 include: Check Engine Light, Poor acceleration, Rough idle, Hesitation, Poor fuel economy.

What causes P1121 on a 2004-2008 Ford F-150?

Common causes of P1121 include: Dirty or faulty MAF sensor, Faulty TP sensor, Vacuum leak, Restricted air filter, Intake air leak.

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