Chery A11 2003, Repair Manual, Page: 237 / 784

CAC Gasoline Engine Maintenance And Servicing Manual
93
Catalytic converter may damp the three contaminations in the exhaust: unburned hydrocarbon (HC), carbon
monoxide(CO) and nitrogen oxide (NO
X
).
two kinds of complicated chemical reactions exist in the catalytic converter: the oxidation of carbon
monoxide and hydrocarbon changing into carbon dioxide and water; nitrogen oxide changing into nitrogen.
note
：
Using leaded gasoline may damage the catalytic converter and weaken its catalytic capability so that
it does not function completely for the system. And the damage is irremediable. The weakening of the catalytic
converter capability for the chemical reaction should not occur within 80 thousand kilometers or five years.
Besides lead, the unburned fuel in the converter is another factor for the catalytic converter failure.
In the catalytic converter, the temperature is 800
℃
. Even so
，
if fuel only remains in the converter for 30
seconds , the combustion caused by the fuel will damage the converter .sometimes, a few-second stay of the
fuel in the converter may result in irremediable damage. Therefore, it is very necessary to insure the ignition
system high performance.
during repairing and testing, be sure to avoid unplugging the spark wire when engine is operating. If it is
needed to do this kind of test, it is suggested to replace the converter temporarily with a pipe and perform the
test.
1. fuel tank (with sealing fuel tank cap) 2. Two-way check valve
3. injection/ ignition (ECU) 4. Multi-function valve
5.charcoal canister(in the engine compartment) 6. fuel vapor recirculation solenoid
7.throttle valve body
8. Expansion chamber
the fuel tank ventilation style applied on the system is
“
close loop
”
type. It prevents the vapor coming
from the fuel tank and fuel supply system from emitting into the atmosphere. thus the small quantity of carbon
compound in the fuel vapor is prevented from emitting and polluting the atmosphere .
The operation during engine doesn
’
t run (figure. 154)
Fig.153 part position of anti-fuel vaporization system
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