P019B

O2 Sensor Delayed Response - Lean to Rich Bank 1 Sensor 3

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

Increased fuel consumption
Deterioration in engine dynamics
Unstable idle
Check Engine Light Is On

Causes

Oxygen sensor malfunction (Bank 1 Sensor 3)
Damaged or corroded sensor wiring harness
Poor contact in the sensor connector
Leaks in the exhaust system
Problems with the fuel system (injectors, fuel pump)

How to Fix

Check the condition of the oxygen sensor and its connector
Inspect the wiring harness for damage
Check the exhaust system for leaks
Test the fuel system (pressure, injectors)
If necessary, replace the oxygen sensor

Related codes

P0137 P0138 P0171 P0172 P0420