EMS 5002 Operator's Manual page 25

Exhaust gas analyzers can be used to diagnose driveability concerns, ignition system prob-
lems, fuel management issues, engine mechanical problems, excessive emissions problems
and many other vehicle systems. Vehicle inspection and preparation are the keys to getting the
most out of your gas analyzer.
1. A visual inspection should include; vacuum hoses, air filter, exhaust system, air
management system, emission related components, etc. If the malfunction
indicator light (MIL) is illuminated, check the diagnostic trouble codes (DTC's)
prior to testing.
2. Vehicle preparation:
Understanding the relationship of exhaust gases will enhance your ability to diagnose
driveability issues. The Exhaust Gas Relationship Chart will provide a few suggestions:
Exhaust gas analyzers can be used to diagnose other vehicle systems. Here are a
few suggestions:
1. Evaporative emission system operation.
2. Evaporative emission system leaks.
3. Fuel oders in and around the vehicle.
4. No-Start conditions.
5. Engine combustion gases in the cooling system.
6. Air injection emission systems.
7. Exhaust system leaks.
8. More...
Diagnostics
a. The engine should be at operating temperature prior to testing.
b. Start the engine and run until the cooling fan cycles on and off. Another
option is using a scan tool to check the engine coolant temperature (ECT).
The temperature should exceed 190 degree F.
c. After the engine is warm, increase the engine speed to 2500 RPM for
approximately 60 seconds.
d. Return the engine speed to idle.
e. Insert the sample probe and begin your diagnostics.
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