Mitsubishi Eclipse 1990 Service Manual page 563

Code No. Evaporative Emission
Detected Malfunction
[Comment]
Background
The engine control module turns the evaporative emission ventilation solenoid on in order
to shut off the outside air
Next, the evaporative emission purge solenoid is driven at the specified duty (approximately
25%) to generate a negative pressure in the fuel tank and purge line, etc.
When a negative pressure is generated in the fuel tank and purge line, etc., the evaporative
emission purge solenoid turns off and the fuel tank and purge line, etc. are sealed.
After they are sealed, monitoring of pressure differences inside the fuel tank starts, and
if there is a large drop in pressure over a given time (if the negative pressure is leaking
out into the atmosphere and the pressure has approached barometric pressure), the engine
control module judges that there is a leak in the fuel tank, purge line or vapor line.
Furthermore, if the fuel tank internal pressure does not drop even if the evaporative emission
purge solenoid is driven while the outside air
of a blockage in the purge line or because the fuel tank filler tube cap has not been
tightened correctly), the engine control module judges that there is a problem with the
system and the check engine/malfunction indicator lamp illuminates.
Check Area
Engine coolant is not lower than
Engine speed is at between 1600
Power steering pressure switch: OFF
Ambient pressure is not lower than 76
Volumetric efficiency: 20
Intake air temperature is not lower than
Pressure increase when evaporative emission purge solenoid and evaporative emission
ventilation solenoid are closed is 50
Pressure variation range is 66
Monitoring time: 50 100 sec.
Criteria
Internal pressure of the fuel tank has not changed more than 100
the tank and vapor line were closed.
Check if the fuel tank filler tube cap is attached correctly.
SCAN TOOL Actuator test
06 Evaporative emission purge solenoid (Refer to
SCAN TOOL Actuator test
29 Evaporative emission ventilation solenoid (Refer to
SCAN TOOL Data list
73 Fuel tank differential pressure sensor (Refer to
SCAN TOOL Data list
21 Engine coolant temperature sensor (Refer to
SCAN TOOL list
13 Intake air temperature sensor (Refer to
27 Power steering pressure switch (Refer to
Check for contamination (water, kerosene, etc.) in the fuel.
have failed. [Refer to the Emission Diagnosis Manual (Pub.
ENGINE (TURBO)
AND ENGINE>
Engine>
of the evaporative emission canister.
of the canister is shut off (because
3500
(11.0 psi).
or less.
or less.
OK
OK
OK
OK
OK
OK
OK
Revision
Troubleshooting
System
Probable cause
in 20 after
NG
Attach correctly.
N G
Repair or replace
Check the evaporative emission control system purge control valve
circuit malfunction (Refer to
DURE FOR DIAGNOSTIC TROUBLE CODE
NG
Check the evaporative emission control system vent control
function (Refer to
DIAGNOSTIC TROUBLE CODE
N G
Check the evaporative emission control system pressure sensor
DIAGNOSTIC TROUBLE CODE
Check the engine coolant temperature sensor circuit malfunction
TIC TROUBLE CODE
N G
Check the intake air temperature sensor circuit malfunction (Refer
to INSPECTION PROCEDURE
TROUBLE CODE
Check the power steering pressure sensor circuit range/perfor-
mance (Refer to
DIAGNOSTIC TROUBLE CODE
Improper tightening of fuel tank filler tube cap
Fuel vent valve failed
Purge line or
Broken seal in fuel purge line or vapor
line
Evaporative emission, purge solenoid failed
Evaporative
,
failed
Fuel tank differential
Engine coolant temperature sesnor failed
Intake air temperature sensor failed
Power steering pressure switch failed
Incorrect fuel used
INSPECTION
INSPECTION PROCEDURE FOR
INSPECTION PROCEDURE FOR
solenoid
failed
.
DIAGNOSTIC