P016B

Closed Loop Air/Fuel Ratio Control At Limit - System Too Rich

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

Increased fuel consumption
Reduced engine power
Black smoke from the exhaust pipe
Unstable engine idling

Causes

Malfunction of oxygen sensors
Fuel leakage through injectors
Increased pressure in the fuel rail
Dirty or faulty air flow sensor
EVAP system malfunction
Mechanical engine problems (piston group wear)

How to Fix

Check oxygen sensor readings using a scanner
Check fuel injectors for leaks
Measure the pressure in the fuel rail
Check the condition and readings of the mass air flow sensor
Check the EVAP system for leaks
If necessary, replace faulty components

Related codes

P0172 P0175 P2196 P2198