Mercedes-Benz Sprinter: OM642 3.0 V6 EGR Cooler Internal Cracking

The EGR cooler fitted to the OM642 3.0-litre V6 diesel is prone to internal cracking, allowing engine coolant to enter the exhaust gas recirculation circuit and be drawn into the intake manifold. Mercedes-Benz issued Technical Service Bulletin LI14.20-N-073813 addressing EGR system faults on this engine and mandating cooler and valve replacement when electrical faults are present. Wet soot accumulation accelerates cooler deterioration. If coolant enters combustion chambers in sufficient quantity, hydrolock or head gasket damage can result.

• White or sweet-smelling exhaust smoke from tailpipe
• Coolant level dropping without visible external leak
• P0400 or P0401 EGR flow fault codes on scan tool
• Wet or tar-like black soot visible inside EGR pipework or intake manifold

1. 1

   Inspect EGR cooler outlet pipework and intake manifold entry for wet or tar-like black soot — wet, oily soot is a specific indicator of coolant leaking past the cooler.

2. 2

   Check coolant reservoir for oil contamination and note coolant level history.

3. 3

   Connect scanner and read for EGR-related fault codes.

4. 4

   Inspect intake manifold runners for carbon or soot deposits.

Parts involved: EGR valve.

≈A$1,380 to ≈A$3,500 at independent workshop rates, shown as an approximate guide in Australian dollars. That is for this job on its own, not for the car.

An estimate, converted to Australian dollars, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has the EGR cooler or EGR valve been replaced?”
• “Has the vehicle ever produced white smoke or lost coolant without an obvious leak?”
• “Are there any stored EGR-related fault codes?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.