Failure mode - Mercedes-Benz 3.0L V6 Diesel (Sprinter 2007-2022)

EGR valve and intake coking

Reliability tier: aggregated - verify before ordering, see /disclosure/

Symptoms

EGR flow DTCs, rough idle and haze on cold start
gradual power loss and higher EGTs as the intake cakes up
check engine light after short-trip duty cycles

Compare with the other causes of the same sign on this engine: loss of power, limp mode or derate (4 causes) · misfire, rough idle, hesitation or surging (4 causes)

Root cause

Exhaust recirculation on a high-EGR van diesel cokes the valve and the intake path; the OM642 community service pattern is periodic EGR pipe/intake decarbonizing (the short EGR pipe gives access for cleaner treatment). NHTSA has a small EGR cluster (6 complaints, 2007-2011 era-heavy) - thin but real; the service pattern carries the weight.

Diagnosis

read EGR DTCs and command the valve; check feedback position vs commanded
pull the EGR pipe and inspect the valve pintle and intake ports for coking
clean per procedure (the EGR pipe is the service access point); retest for flow codes

Fixes

EGR valve/intake decarbonizing service; valve replacement when the pintle no longer seals or positions ()

egr-valve - more than one option: OM642 EGR Changeover Flap (642-140-03-00-64, current), OM642 EGR Valve (642-140-14-60-64), OM642 EGR Valve Gasket (642-142-23-80)
OM642 EGR Cooler / Heat Exchanger (642-140-21-75, current)

Prevalence

common