B2971 Engine Trouble Code
What is B2971?
When B2971 code appears, first check your gas cap. Pull over safely, ensure it is tight, and inspect for cracks. A loose or damaged gas cap affects fuel-system pressure and emissions. A replacement cap costs about $3–$10. This simple fix can resolve the code and improve fuel economy.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Code: | B2971 |
B2971 Symptoms
Check Engine Light
Illuminated dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration
Starting Problems
Difficulty starting the engine
B2971 Code Structure
Understanding what each digit means in the B2971 body trouble code:
| B | 2 | 9 | 7 | 1 |
|---|---|---|---|---|
| Body Code | Fuel And Air Metering (Injector Circuit Malfunctions Only) | Injector Circuit Malfunction - Cylinders | Cylinder 10 Contribution/Balance Fault | Crankshaft Position Sensor A Circuit Low Input |
How to Fix B2971
Diagnostic Steps:
Oxygen sensors measure exhaust gas oxygen content to optimise air-fuel ratio. This optimisation improves fuel economy and reduces emissions. Sensors degrade over time and require periodic replacement.
Repair Solution:
A/C pressure sensor monitors refrigerant pressure changes. DTC sets when pressure change falls outside calibration. Verify A/C system function, refrigerant charge, and electrical connections.
Technical Notes:
For B2971, verify VCT solenoid operation. Look for stuck or sticking valves caused by contamination. Consult vehicle-specific repair manual for proper component testing procedures.
B2971 Description
B2971 engine trouble code is related to Crankshaft Position Sensor A Circuit Low Input.
Main Cause
The primary reason for B2971 OBD-II Engine Trouble Code is: Injector Circuit Malfunction - Cylinders.