Audi DTC P1128 – Long Term Fuel Trim multiplier, Bank1 System too Lean
DTC P1128 meaning on Audi
The Diagnostic Trouble Code (DTC) P1128 on an Audi indicates that the Long Term Fuel Trim multiplier for Bank 1 is too lean. This means that the engine control module (ECM) has detected a lean air-fuel mixture condition in the fuel system of the vehicle.
Audi DTC P1128 symptoms
Symptoms of DTC P1128 on an Audi may include:
- Check Engine Light (CEL) illuminated on the dashboard
- Decreased fuel efficiency
- Engine hesitation or misfiring
- Rough idling or stalling
Audi DTC P1128 causes
Common causes of DTC P1128 on an Audi include:
- Vacuum leaks in the intake system
- Faulty oxygen sensor
- Clogged fuel injectors
- Dirty or clogged air filter
- Fuel pressure regulator issues
Audi DTC P1128 seriousness
While DTC P1128 may not cause immediate harm to the engine, it can lead to decreased fuel efficiency and potential long-term damage if left unresolved. It is important to diagnose and fix the issue promptly to prevent further complications.
How to diagnose DTC P1128 on Audi
To diagnose DTC P1128 on an Audi, you can perform the following steps:
- Use an OBD-II scanner to retrieve the fault code and freeze frame data
- Inspect the intake system for any vacuum leaks
- Check the oxygen sensor for proper functioning
- Clean or replace the air filter
- Test the fuel injectors for clogs or malfunctions
How to fix DTC P1128 on Audi
To fix DTC P1128 on an Audi, you can try the following solutions:
- Repair any vacuum leaks in the intake system
- Replace the faulty oxygen sensor
- Clean or replace clogged fuel injectors
- Replace the air filter if dirty or clogged
- Check and repair any issues with the fuel pressure regulator
How to erase DTC P1128 on Audi
After fixing the underlying issue causing DTC P1128 on an Audi, you can erase the fault code using an OBD-II scanner. Simply clear the code from the ECM’s memory, and if the issue has been successfully resolved, the Check Engine Light should turn off.
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