Mercedes Benz V6 diesel
Common malfunctions are listed below together with probable causes and
remedial actions. Fuel-related malfunctions can affect the color of the exhaust
smoke.When taken together, engine behavior and smoke
color provide a good indication of the source of the problem.
Engine cranks slowly, does not start
Starting system malfunction---Recharge batteries if cranking voltage drops
below 9.5V or electrolyte reads less than 1.140when tested with a hydrometer. Clean battery terminals.
High parasitic loads---Check for binds in driven equipment, overly tight
drive belts, shaft misalignments.
Crankshaft viscosity bound---Dark, sticky residue on the dipstick can indicate
presence of antifreeze (ethylene glycol) in oil.Have oil analyzed.
Engine cranks normally, does not start
EMS sensor or actuator failure ---Retrieve trouble codes
No fuel to injectors--- Check for restrictions or air leaks in fuel system,low injector pressure.Glow-plug failure--- Check glow-plug supply circuit, glow-plug controlmodule and individual plugs. Air inlet restriction---Replace air filter element.
Exhaust restriction--- Inspect piping, if necessary perform backpressure test.
Engine starts normally, runs no more than a minute or two,and shuts downAir in fuel--- Bleed system and check for air leaks.
Fuel return line restricted Disconnect line to verify flow and remove obstruction.Air inlet restriction--- Replace filter element.Clogged fuel filter --Replace filter element.
Whitish or blue smoke at high Ispeed and light load, especially rwhen engine is cold. As temperature rises, smoke color changes to black. Power loss across the rpm band, especially at full throttle.===Injector pump timing retarded.
Persistent blue smoke at all speeds, loads and operating temperatures.===Worn rings/cylinders. Overhaul/rebuild engine.
Light blue or whitish smoke athigh speed under light load. Pungent odor.====Over-cooling. Replace thermostat.