P1121 – Ford DTC

Ford DTC P1121 – Throttle Position Sensor Inconsistent with Mass Air Flow Sensor

DTC P1121 meaning on Ford

DTC P1121 on a Ford indicates that there is an inconsistency between the throttle position sensor (TPS) and the mass air flow (MAF) sensor readings. The Engine Control Module (ECM) detects this discrepancy, which can affect the engine’s performance.

Ford DTC P1121 symptoms

Symptoms of DTC P1121 on a Ford may include:

• Check Engine Light (CEL) illuminated
• Reduced engine power
• Poor acceleration
• Stalling or rough idling

Ford DTC P1121 causes

Common causes of DTC P1121 on a Ford include:

• Faulty throttle position sensor
• Malfunctioning mass air flow sensor
• Wiring or connector issues between the sensors and ECM
• Dirty or clogged air filter

Ford DTC P1121 seriousness

DTC P1121 should not be ignored as it can lead to drivability issues and potential engine damage if left unresolved. It is recommended to address this issue promptly to prevent further complications.

How to diagnose DTC P1121 on Ford

To diagnose DTC P1121 on a Ford, you can:

1. Use an OBD-II scanner to retrieve the trouble codes
2. Inspect the throttle position sensor and mass air flow sensor for any visible damage
3. Check the wiring and connectors for any signs of wear or corrosion
4. Perform a voltage and resistance test on the sensors

How to fix DTC P1121 on Ford

To fix DTC P1121 on a Ford, you may need to:

1. Replace the faulty throttle position sensor or mass air flow sensor
2. Repair or replace any damaged wiring or connectors
3. Clean or replace the air filter if necessary
4. Clear the trouble codes and reset the ECM

How to erase DTC P1121 on Ford

To erase DTC P1121 on a Ford, you can:

1. Use an OBD-II scanner to clear the trouble codes
2. Disconnect the battery for a few minutes to reset the ECM
3. Drive the vehicle for a short distance to allow the ECM to relearn the sensor values

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