B2979 Engine Trouble Code
What is B2979?
B2979 code can indicate a faulty oxygen sensor, which may eventually damage the catalytic converter (repair cost: $2,000–$2,200). Professional diagnosis costs around $200–$210. Oxygen sensors are often straightforward to replace — check your owner's manual for location and instructions. This issue should be addressed promptly to prevent further damage.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Code: | B2979 |
B2979 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
B2979 Code Structure
Understanding what each digit means in the B2979 body trouble code:
| B | 2 | 9 | 7 | 9 |
|---|---|---|---|---|
| Body Code | Fuel And Air Metering (Injector Circuit Malfunctions Only) | Injector Circuit Malfunction - Cylinders | Cylinder 10 Contribution/Balance Fault | Reverse Input Circuit |
How to Fix B2979
Diagnostic Steps:
Regarding B2979, carefully inspect the wire harness near the intake manifold bracket, best accessed from below near the oil filter. Look for chafing, pinching, or damaged insulation.
Repair Solution:
Crankshaft position sensor signals the computer for precise ignition and fuel injection timing. Faulty sensors cause rough running and reduced efficiency. Modern vehicles enter limp mode and illuminate the check-engine light.
Technical Notes:
Parts or components should not be replaced based solely on B2979 DTC. Consult your vehicle service manual for proper diagnostic procedures, possible causes, and required testing before replacement.
B2979 Description
B2979 engine trouble code is related to Reverse Input Circuit.
Main Cause
The primary reason for B2979 OBD-II Engine Trouble Code is: Injector Circuit Malfunction - Cylinders.