Be careful when performing
this test. Exhaust gas can
be extremely hot and severe
burns can result.
Put a piece of paper in the exhaust stream for a few
moments with the engine at idle. Then look at the paper
to see if there is any condensed fuel on it. Then smell
the paper to see if it smells like raw fuel. If it smells like
fuel, the engine could be very cold or else it has a DS
level fuel system fault or compression fault.
White smoke for a short time after start-up,
especially on a cold day, is a normal condition.
It is caused by incomplete combustion of the
fuel because of low cylinder temperature.
should clear up in a few minutes. If not, you
may have a bad head gasket, cracked block,
or a restricted check valve. Check for
restricted check valve (para. 3-36).