Volkswagen DTC P1139 – Long Term Fuel Trim Additional Fuel B2 System Too Rich
DTC P1139 meaning on Volkswagen
DTC P1139 on a Volkswagen indicates that the Long Term Fuel Trim Additional Fuel Bank 2 system is detecting a fuel mixture that is too rich. This means that there is an excessive amount of fuel being delivered to the engine in relation to the amount of air present, leading to a rich air-fuel mixture.
Volkswagen DTC P1139 symptoms
Symptoms of DTC P1139 on a Volkswagen may include:
- Decreased fuel efficiency
- Black smoke from the exhaust
- Rough idling or stalling
- Check Engine Light illuminated
Volkswagen DTC P1139 causes
The common causes of DTC P1139 on a Volkswagen include:
- Faulty oxygen sensor
- Leaking fuel injectors
- Dirty or clogged air filter
- Issues with the fuel pressure regulator
Volkswagen DTC P1139 seriousness
While DTC P1139 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.
How to diagnose DTC P1139 on Volkswagen
To diagnose DTC P1139 on a Volkswagen, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the fault code
- Inspect the oxygen sensor for proper operation
- Check for any fuel leaks or issues with the fuel injectors
- Inspect the air filter and intake system for any obstructions
How to fix DTC P1139 on Volkswagen
To fix DTC P1139 on a Volkswagen, the following steps may be taken:
- Replace the faulty oxygen sensor
- Clean or replace any clogged fuel injectors
- Replace the air filter if dirty
- Check and adjust the fuel pressure regulator if necessary
How to erase DTC P1139 on Volkswagen
After fixing the underlying issue causing DTC P1139 on a Volkswagen, the fault code can be erased using a diagnostic scanner. This will reset the Check Engine Light and clear the code from the vehicle’s memory.
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