BMW DTC P1278 – Engine Smoothness Control Correction Quantity Too High
DTC P1278 meaning on BMW
DTC P1278 on a BMW indicates that the Engine Smoothness Control Correction Quantity is too high. This means that the engine control module has detected that the correction value for maintaining engine smoothness is exceeding the predetermined threshold.
BMW DTC P1278 symptoms
Symptoms of DTC P1278 on a BMW may include rough idling, engine hesitation, decreased fuel efficiency, and potentially even stalling. The Check Engine Light may also be illuminated on the dashboard.
BMW DTC P1278 causes
The common causes of DTC P1278 on a BMW can include issues with the fuel system such as a clogged fuel filter, a malfunctioning fuel pump, or a faulty fuel pressure regulator. It can also be triggered by problems with the air intake system, such as a dirty air filter or a vacuum leak.
BMW DTC P1278 seriousness
While DTC P1278 may not always result in immediate engine failure, it can lead to poor engine performance and potentially cause damage over time if left unresolved. It is advisable to address this issue promptly to prevent further complications.
How to diagnose DTC P1278 on BMW
To diagnose DTC P1278 on a BMW, a mechanic would typically use a diagnostic scanner to retrieve the fault codes stored in the engine control module. They would then perform a thorough inspection of the fuel and air intake systems to identify any potential issues causing the high correction quantity.
- Use a diagnostic scanner to retrieve fault codes
- Inspect the fuel system components
- Check the air intake system for any leaks or blockages
How to fix DTC P1278 on BMW
Fixing DTC P1278 on a BMW involves addressing the root cause of the high correction quantity. This may include replacing a clogged fuel filter, repairing a vacuum leak, or fixing a faulty fuel pressure regulator. Once the underlying issue is resolved, the fault codes can be cleared from the engine control module.
- Replace the fuel filter
- Repair any vacuum leaks
- Fix or replace the fuel pressure regulator
How to erase DTC P1278 on BMW
To erase DTC P1278 on a BMW, the fault codes stored in the engine control module can be cleared using a diagnostic scanner. Once the repairs have been made to address the underlying issue causing the fault code, the codes can be reset to turn off the Check Engine Light.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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