P21F8

Fuel Control System B Too Lean at Idle Bank 1

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$17–89 (est.)

Symptoms

Unstable engine idling
Power Loss
Increased fuel consumption
Check Engine light comes on
Dips during acceleration

Causes

Air leaks in the intake tract
Malfunction of oxygen sensors
Clogged fuel injectors
Weak fuel pump
EGR system malfunction

How to Fix

Check the intake tract for air leaks
Check the operation of oxygen sensors
Clean or replace fuel injectors
Check fuel pressure and pump operation
Diagnose the EGR system

Related codes

P2177 P2187 P2191