P21FD

Fuel Control System B Too Rich at Higher Load Bank 1

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$17–89 (est.)

Symptoms

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

Causes

Fuel injector malfunction
Problems with the oxygen sensor (lambda probe)
Vacuum leak in the intake system
Fuel pressure regulator malfunction
Contamination or malfunction of the mass air flow sensor (MAF)

How to Fix

Check the condition of the fuel injectors
Diagnostics of oxygen sensors
Check the intake system for vacuum leaks
Check fuel pressure and pressure regulator
Clean or replace the mass air flow sensor

Related codes

P2178 P2195 P2196 P0172