Excess black or dark grey smoke under load (incomplete combustion)

 Noticeable loss of power
Possible causes: Faulty Turbocharger.

 Apparent at low to medium speed, power may be down.
Possible causes: Clogged fuel lines.

 Apparent at low to medium speed, engine noisier than usual.
Possible causes: Injector pump time advanced.

 Apparaent at medium to high speed, power may be down.
Possible causes: Dirty injector, nozzle.

 Apparaent at medium to high speed, engine quieter than usual.
Possible causes: Injector pump timing retarded.

 Most noticeable at full load.
Possible causes: Dirty primary, secondary air filter.

 Smoke in puffs, at times with blue or white component. Knocking.
Possible causes: Sticky injectors.

Blue smoke (oil consumption)

 Under acceleration after prolonged period at idle, may disappear under steady throttle.
Possible causes: Worn valve products / leaking valve seals.

 Persistent at all speeds, loads and temperature.
Possible causes: Worn rings / cylinder liners.

White Smoke

 Water in combustion chamber or incomplete combustion at startup.
Possible causes: Damaged cylinder head / leaking head gasket / damaged cylinder liners.

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