BMW DTC P140A – Secondary Air Injection System Insufficient Total Flow (Bank 1 and Bank 2)
DTC P140A meaning on BMW
The DTC P140A code on a BMW indicates a problem with the Secondary Air Injection System, specifically pointing to insufficient total flow on both Bank 1 and Bank 2. This system is responsible for reducing harmful emissions by injecting fresh air into the exhaust system during cold engine starts.
BMW DTC P140A symptoms
Symptoms of a DTC P140A on a BMW may include:
- Check Engine Light (CEL) illuminated
- Decreased engine performance
- Increased emissions
- Engine stalling or rough idling
BMW DTC P140A causes
Common causes of a DTC P140A on a BMW include:
- Faulty Secondary Air Injection Pump
- Blocked or restricted air passages
- Malfunctioning Secondary Air Injection Valves
- Wiring or electrical issues
BMW DTC P140A seriousness
While a DTC P140A may not cause immediate drivability issues, it can lead to increased emissions and potential long-term engine damage if left unresolved. It is important to address this code promptly to maintain the vehicle’s performance and environmental compliance.
How to diagnose DTC P140A on BMW
To diagnose a DTC P140A 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 blockages
- Check the operation of the Secondary Air Injection Pump and Valves
- Test the electrical connections and wiring related to the system
How to fix DTC P140A on BMW
To fix a DTC P140A on a BMW, the following steps may be taken:
- Replace the faulty Secondary Air Injection Pump or Valves
- Clean out any blockages in the air passages
- Repair or replace damaged wiring or electrical connections
- Clear the fault codes and reset the Check Engine Light
How to erase DTC P140A on BMW
To erase a DTC P140A on a BMW, the fault codes can be cleared using a diagnostic scanner. After addressing the underlying issue causing the code, the scanner can be used to reset the Check Engine Light and ensure that the code does not reappear.
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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