1993 GMC SIERRA sensor

6. Close the water drain valve and connect a hose going from the air bleed\

valve port
to a fuel-resistant container. The inside diameter of the hose
should be one-eighth of an inch.
for the starter to cool.
Do this until you can see clear fuel coming from
the air bleed valve.
7. Turn your ignition key to Start for 10 to 15 seconds. Wait one minute
8. Close the air bleed valve and replace the fuel tank cap.
9. Start your engine and let it idle for five minutes. Be sure to check your
fuel filter for leaks.
Fuels in Foreign Countries (Gasoline Engines)
If you plan on driving in another country outside the US. or Canada,
unleaded fuel may be hard to find.
Do not use leaded gasoline. If you use
even one tank full, your emission controls won’t work well \
or at all. With
continuous use, spark plugs can get fouled, the exhaust system \
can corrode,
and your engine oil can deteriorate quickly. Your vehicle’s three-way catalytic
converter and oxygen sensor will be damaged.
All of that means costly
repairs that wouldn’t be covered by your warranty.
To check on fuel availability, ask an auto club, or contact a major oil
company that does business in the country where you’ll be driving.
You can also write us at the following address for advice. Just tell us where
you’re going and give your Vehicle Identification Number (VIN).
General Motors of Canada Ltd.
International Export Sales
Post Office Box
828
Oshawa, Ontario L1H 7N1, Canada
6-1 5
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you use leaded fuel, you could damage your three-way catalytic converter,
and other engine components.
Computer Command Control System (All TBI equipped
vehicles and diesel engine vehicles below
8,500 lbs. GVWR)
Gasoline Engines
This system has an oxygen (OS) sensor that helps keep your engine’s air-fuel
mixture at a proper level. Use only unleaded fuel in your veh\
icle.
If you use
leaded fuel, you could damage your oxygen
(OS) sensor and three-way
catalytic converter.
Diesel Vehicles Below 8,500 LBS. GVWR
This system monitors engine speed and throttle position. It adj\
usts exhaust gas recirculation to limit emissions.
The Malfunction Indicator Lamp
(SERVICE ENGINE SOON) on your
instrument panel lets you know when your emission control syste\
m needs
service. The light will come on briefly when you start your e\
ngine to let you
know that the system is working. If
it does not come on when you start your
engine, or
if it comes on and stays on while you’re driving your system may \
need service. Your vehicle should still be driveable, but you should have your
system serviced right away.
Secondary Air Injection (AIR) System
You may have this system. It lets you know if your engine control module,
wiring harness or solenoid need service.
If the Malfunction Indicator Lamp
(Service Engine Soon) comes on, you need service.
6-66
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