Audi DTC P1123 – Long Term Fuel Trim Additional Air, Bank1 System too Rich
DTC P1123 meaning on Audi
The Diagnostic Trouble Code (DTC) P1123 on an Audi indicates that the Long Term Fuel Trim Additional Air, Bank1 System is too rich. This means that the engine control module (ECM) has detected that the air-fuel mixture in the engine is too rich, meaning there is too much fuel being injected relative to the amount of air entering the engine.
Audi DTC P1123 symptoms
Symptoms of DTC P1123 on an Audi may include:
- Decreased fuel efficiency
- Black smoke from the exhaust
- Rough idling or stalling
- Engine hesitation or misfiring
- Check Engine Light (CEL) illuminated on the dashboard
Audi DTC P1123 causes
Common causes of DTC P1123 on an Audi include:
- Faulty oxygen sensor
- Dirty or clogged fuel injectors
- Vacuum leaks in the intake system
- Malfunctioning mass airflow sensor (MAF)
- Issues with the fuel pressure regulator
Audi DTC P1123 seriousness
While DTC P1123 may not cause immediate harm to the engine, it can lead to decreased fuel efficiency and increased emissions. Ignoring this issue can potentially cause damage to the catalytic converter over time and may result in more severe engine problems if left unresolved.
How to diagnose DTC P1123 on Audi
To diagnose DTC P1123 on an Audi, a mechanic would typically perform the following steps:
- Use an OBD-II scanner to retrieve the fault codes
- Inspect the oxygen sensor for proper operation
- Check the fuel injectors for clogs or leaks
- Inspect the intake system for vacuum leaks
- Test the mass airflow sensor (MAF) for proper function
How to fix DTC P1123 on Audi
To fix DTC P1123 on an Audi, the following steps may be taken:
- Replace the faulty oxygen sensor
- Clean or replace clogged fuel injectors
- Repair any vacuum leaks in the intake system
- Replace the malfunctioning mass airflow sensor (MAF)
- Address any issues with the fuel pressure regulator
How to erase DTC P1123 on Audi
After fixing the underlying issue causing DTC P1123 on an Audi, the fault codes can be cleared using an OBD-II scanner. This will reset the Check Engine Light (CEL) and erase the DTC from the vehicle’s memory. It is important to ensure that the issue has been properly addressed before clearing the fault codes.
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