Mitsubishi ECLIPSE Technical Information Manual

ENGINE <NON-TURBO> - Emission Control System
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EVAPORATIVE EMISSION CONTROL SYSTEM
N71AP03AA
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The evaporative emission control system prevents
the emission of fuel tankvapors into the atmosphere.
When fuel evaporates in the fuel tank, the vapors
pass through vent hoses or tubes to the charcoal
filled EVAP canister. The EVAP canister temporarily
holds the vapors. Through the EVAP purge solenoid,
the power-train control module (PCM) allows intake
manifold vacuum to draw vapors into the combustion
chambers during certain operating conditions. The
solenoid regulates vapor flow from the canister to
the engine.
OPERATION
The EVAP purge solenoid regulates the rate of vapor
flow from the EVAP canister to the throttle body.
The PCM operates the solenoid.
During the cold start warm-up period and the hot
start time delay, the PCM does not energize the
solenoid. When de-energized, no vapors are purged.
The PCM de-energizes the solenoid during open
loop operation.
The engine enters closed loop operation after it
reaches a specified temperature and the pro-
grammed time delay ends. During closed loop op-
eration, the PCM energizes and de-energizes the
solenoid approximately 5 to 10 times per second,
depending upon operating conditions. The PCM va-
ries the vapor flow rate by changing solenoid pulse
width. Pulse width is the amount of time the solenoid
de-energizes.
PULSED SECONDARY AIR INJECTION SYSTEM
N71AP03AA
Only manual transaxle vehicles have a pulsed sec-
OPERATION
ondary air injection system. The system injects fresh
air upstream of the catalytic convertor. It operates
The PCM controls the ground path for the solenoid.
for a short period after cold engine start-up until
When the PCM grounds the solenoid, fresh air from
the engine coolant temperature reaches approxi-
the air cleaner flows through the aspirator valve
mately 5% (125°F)
to the catalytic convertor.
The secondary air injection system contains:
The aspirator valve prevents exhaust gases from
flowing into the fresh air stream, at the air cleaner
l Pulsed secondary air injection valve
l Pulsed secondary air injection solenoid
l Connecting hoses and tubes
when the solenoid is grounded. If the aspirator valve
malfunctions, a popping noise could be heard during
cold start throttle stabs.
Pulsed secondary
Pulsed secondary
air injection solenoid
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AFU0015
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Mitsubishi ECLIPSE Specifications

General

Brand	Mitsubishi
Model	ECLIPSE
Category	Automobile
Language	English