B2989 Engine Trouble Code
What is B2989?
B2989 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: | B2989 |
B2989 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
B2989 Code Structure
Understanding what each digit means in the B2989 body trouble code:
| B | 2 | 9 | 8 | 9 |
|---|---|---|---|---|
| Body Code | Fuel And Air Metering (Injector Circuit Malfunctions Only) | Injector Circuit Malfunction - Cylinders | Ignition/Distributor Engine Speed Input Circuit Malfunction | Reverse Input Circuit |
How to Fix B2989
Diagnostic Steps:
Regarding B2989, 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:
Most manufacturers number cylinders sequentially from front to back. Ford V-engines start with cylinder 1 at front left. In V-6 engines, cylinder 4 is front right; in V-8 engines, cylinder 5 occupies that position.
Technical Notes:
For B2989, verify VCT solenoid operation. Look for stuck or sticking valves caused by contamination. Consult vehicle-specific repair manual for proper component testing procedures.
B2989 Description
B2989 engine trouble code is related to Reverse Input Circuit.
Main Cause
The primary reason for B2989 OBD-II Engine Trouble Code is: Injector Circuit Malfunction - Cylinders.