Chevrolet 2008 T Series, Owner'S Manual

Page: 51 / 298

Exhaust Restrictor
If your vehicle is equipped with this feature, there is an
exhaust restrictor valve located in the exhaust stream.
The valve closes to provide back pressure to the engine
for the purpose of warming the engine quickly.
The exhaust restrictor operates:
•
while the engine is running.
•
while the vehicle is not moving.
•
while the accelerator, brake and clutch pedals are
not pressed on a manual transmission vehicle.
•
while idling in cold temperatures.
•
when the shift lever is in NEUTRAL (N) or PARK (P)
on an automatic transmission vehicle.
On vehicles equipped with a diesel engine exhaust
brake, the exhaust brake switch must be on. See
Diesel Engine Exhaust Brake on page 2-16 for more
information. The indicator in the exhaust brake switch will
be lit when the exhaust restrictor is active. The exhaust
brake indicator light in the center of the instrument panel
will also be lit whenever the exhaust restrictor is active.
See Exhaust Brake Indicator Light on page 3-33 for more
information.
When the engine coolant temperature is below
149°F (65°C) and the outside temperature is below
50°F (10°C), the exhaust restrictor will come on within
60 seconds of starting the engine. After running the
engine for an additional 10 seconds, the engine idle
will increase.
The exhaust restrictor will shut off and engine idle will
return to normal once the engine is warmed up, or
the brake pedal is pressed.
Engine Checks Before Operating
When you have started your engine, let it run for
20 to 30 seconds before you put a load on the engine.
But do not leave the vehicle while the engine is running.
Avoid unnecessary idling of diesel engine equipped
vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature causes
several conditions which affect engine operation and
reduce engine life.
The engine should be permitted to go through a
warm-up period. Operate the vehicle at a minimum
of 600 rpm during the warm-up period. During this period
and during operation, the following observations
should be made.
2-13