P1123 Audi Code - Long Term Fuel Trim Adjustment Bank 1 System Too Rich

P1123 indicates that the long-term fuel trim for Bank 1 has detected a system that is running too rich, meaning there is too much fuel in the air-fuel mixture.

Symptoms may include poor fuel economy, black smoke from the exhaust, rough idling, hesitation during acceleration, or the Check Engine Light being illuminated.

Common causes include a faulty mass airflow (MAF) sensor, leaky fuel injectors, a malfunctioning fuel pressure regulator, a restricted air intake, or a defective oxygen sensor.

Yes, a clogged air filter can restrict airflow to the engine, leading to a rich fuel mixture and triggering the P1123 code.

Diagnosis involves checking the MAF sensor, oxygen sensors, fuel injectors, and air intake system for faults or leaks, as well as verifying fuel pressure levels.

Yes, a faulty oxygen sensor can provide incorrect readings to the engine control module, causing it to add excessive fuel and triggering the P1123 code.

While the vehicle may still be drivable, ignoring the P1123 code can lead to reduced fuel efficiency, increased emissions, and potential damage to the catalytic converter.

Potential repairs include cleaning or replacing the MAF sensor, replacing a faulty oxygen sensor, repairing fuel injector leaks, replacing the air filter, or addressing any intake restrictions.

No, vacuum leaks typically cause a lean condition, not a rich condition, so they are unlikely to trigger the P1123 code.

While some causes, like a dirty air filter, can be fixed at home, diagnosing and repairing more complex issues, such as faulty sensors or fuel system problems, may require professional assistance.