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Drift
The Auto600 monitors its change in zero as peak testing progresses and
produces an average drift figure. This is the average change in zero for
every peak test. If the drift figure exceeds 0.05k the test should be
repeated. This may occur on vehicles with high emissions.
What are the causes of excessive smoke?
Smoke is the product of combustion. Vehicles may produce three kinds
of smoke, two of which indicate engine problems. The three types are:
•
Blue smoke (mainly oil and unburnt fuel), which indicates a poorly
serviced and/or tuned engine.
•
Black smoke (soot, oil and unburnt fuel) which indicates a
mechanical fault with the engine or air intake restriction.
•
White smoke (water droplets and unburnt fuel) which is produced
when the engine is started from cold and disappears when the
engine warms up.
With older engines, the white smoke produced has a sharp smell, which
may cause irritation to your upper respiratory system.
What factors effect the composition of diesel smoke emission
The quantity and composition of diesel smoke may vary depending on:
•The quality of diesel fuel used
•The type of engine, e.g. standard, turbo or injector
•The state of engine tuning
•The fuel pump setting
•The workload demand on the engine
•The engine temperature
•Whether the engine has been regularly maintained