P239C

Diesel Intake Air Flow B Control System - High Air Flow Detected

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$17–89 (est.)

Symptoms

Reduced engine power
Unstable engine operation
Increased fuel consumption
Exhaust smoke
Difficulty starting

Causes

Malfunction of the mass air flow sensor (MAF)
Air leaks in the intake tract
EGR valve stuck open
Turbocharging system malfunction
Problems with wiring or sensor connectors

How to Fix

Check the tightness of the intake tract
Diagnose EGR valve operation
Check the readings of the mass air flow sensor
Examine the turbocharging system for malfunctions
Check the integrity of the electrical wiring and sensor contacts

Related codes

P239A P239B P239D