Hyundai DTC P1123 – Long term fuel trim – additive – mixture too rich
DTC P1123 meaning on Hyundai
DTC P1123 on a Hyundai indicates that the Long Term Fuel Trim – Additive – Mixture is too rich. This means that the engine control module (ECM) has detected that the air-fuel mixture is too rich over a long period of time.
Hyundai DTC P1123 symptoms
Symptoms of DTC P1123 on a Hyundai may include:
- Check Engine Light (CEL) illuminated
- Decreased fuel efficiency
- Rough idling or stalling
- Black smoke from the exhaust
Hyundai DTC P1123 causes
Common causes of DTC P1123 on a Hyundai include:
- Faulty oxygen sensor
- Vacuum leaks
- Fuel pressure regulator issues
- Dirty or clogged fuel injectors
Hyundai DTC P1123 seriousness
DTC P1123 should not be ignored as it can lead to poor engine performance, decreased fuel efficiency, and potential damage to the catalytic converter over time if left unresolved.
How to diagnose DTC P1123 on Hyundai
To diagnose DTC P1123 on a Hyundai, a mechanic may perform the following steps:
- Use a scan tool to retrieve the DTC and freeze frame data
- Inspect the oxygen sensor for proper operation
- Check for vacuum leaks in the intake system
- Test the fuel pressure regulator
- Clean or replace fuel injectors if necessary
How to fix DTC P1123 on Hyundai
To fix DTC P1123 on a Hyundai, the following steps may be taken:
- Replace a faulty oxygen sensor
- Repair any vacuum leaks in the intake system
- Replace the fuel pressure regulator if faulty
- Clean or replace clogged fuel injectors
How to erase DTC P1123 on Hyundai
To erase DTC P1123 on a Hyundai, a scan tool can be used to clear the code after the underlying issue has been addressed and fixed. This will reset the Check Engine Light and the DTC from the ECM’s memory.
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