BMW DTC P140C – Secondary Air Injection System Insufficient Total Flow (Bank 1 and Bank 2) and Insufficient Flow (Bank 2)
DTC P140C meaning on BMW
The DTC P140C code on a BMW indicates a problem with the Secondary Air Injection System, specifically pointing to insufficient total flow in Bank 1 and Bank 2, as well as insufficient flow in Bank 2. This system is responsible for reducing harmful emissions by injecting fresh air into the exhaust system to help burn off any remaining fuel before it exits the tailpipe.
BMW DTC P140C symptoms
Symptoms of a DTC P140C code on a BMW may include:
- Check Engine Light illuminated
- Decreased engine performance
- Increased emissions
- Engine misfires
- Rough idling
BMW DTC P140C causes
Common causes of a DTC P140C code on a BMW include:
- Faulty Secondary Air Injection Pump
- Blocked or leaking air injection lines
- Malfunctioning air injection valves
- Electrical issues in the system
BMW DTC P140C seriousness
Ignoring a DTC P140C code on a BMW can lead to increased emissions, potential damage to the catalytic converter, and reduced engine performance. It is important to address this issue promptly to ensure the vehicle operates efficiently and meets emission standards.
How to diagnose DTC P140C on BMW
To diagnose a DTC P140C on a BMW, a mechanic may perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes
- Inspect the Secondary Air Injection System components for damage or leaks
- Test the functionality of the air injection pump and valves
- Check the electrical connections in the system
How to fix DTC P140C on BMW
To fix a DTC P140C on a BMW, the following steps may be taken:
- Replace the faulty Secondary Air Injection Pump
- Clean or replace any blocked or leaking air injection lines
- Repair or replace malfunctioning air injection valves
- Address any electrical issues in the system
How to erase DTC P140C on BMW
After fixing the underlying issue causing the DTC P140C code on a BMW, the code can be erased using a diagnostic scanner. This will reset the Check Engine Light and clear the code from the vehicle’s memory. It is important to ensure that the repair has been successful before erasing the code to prevent it from reoccurring.
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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