B1981 Engine Trouble Code
What is B1981?
With B1981, you may drive for several weeks with a malfunctioning MAF sensor, but expect decreased fuel economy and eventual stalling. Shop replacement costs $240–$400 depending on vehicle. The labour is straightforward, with most cost from the part itself.
Code Information
| Code Type: | OBD-II Body (B) Trouble Code |
| System: | Body |
| Code: | B1981 |
B1981 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
B1981 Code Structure
Understanding what each digit means in the B1981 body trouble code:
| B | 1 | 9 | 8 | 1 |
|---|---|---|---|---|
| Body Code | Fuel And Air Metering | Injector Circuit Malfunction - Cylinders | Ignition/Distributor Engine Speed Input Circuit Malfunction | Crankshaft Position Sensor A Circuit Low Input |
How to Fix B1981
Diagnostic Steps:
Poor running symptoms align with MAP sensor malfunction. In some cases, a faulty MAP sensor will not trigger a code. The issue may represent separate wiring concerns requiring individual diagnosis.
Repair Solution:
Brake switch circuit concerns may involve open or shorted BPP circuits, damaged switches, or misadjustment. Verify stoplight function and follow proper self-test procedures per service manual.
Technical Notes:
B1981 DTC indicating a sensor fault does not always mean the sensor itself is bad. The issue may stem from the systems being monitored or even the sensor wiring. Proper diagnosis is essential.
B1981 Description
B1981 engine trouble code is related to Crankshaft Position Sensor A Circuit Low Input.
Main Cause
The primary reason for B1981 OBD-II Engine Trouble Code is: Injector Circuit Malfunction - Cylinders.