Mitsubishi Galant. Manual — part 275

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-325

STEP 6. Check the evaporative emission ventilation
solenoid using the scan tool MB991502. (Actuator test item
29)
(1) Turn the ignition switch to the "ON" position, remove the

module bracket mounting volts and disconnect hose G from
the evaporative emission ventilation solenoid side.

(2) Connect the hand vacuum pump to the nipple of the

evaporative emission ventilation solenoid from which the
hoses have been disconnected.

(3) Apply a vacuum on the hand vacuum pump, and confirm

that pressure is applied.
If the vacuum is maintained, refer to

P.13B-286

,

evaporative emission ventilation solenoid trouble code DTC
P0446.

(4) Drive the evaporative emission ventilation solenoid with the

scan tool MB991502 actuator test, and confirm that the
vacuum does not fluctuate when the vacuum is applied with
the hand vacuum pump.

Q: Does the vacuum pump gauge reading return to the

atmospheric pressure when the evaporative emission
ventilation solenoid valve is activated?
The evaporative emission ventilation solenoid valve
operates normally and the vacuum pump gauge reading
does not fluctuate : Go to Step 7.
The evaporative emission ventilation solenoid valve
operates normally, but the vacuum can not be
maintained : Replace the evaporative emission ventilation

solenoid. Then go to Step 32.

The evaporative emission ventilation solenoid valve
does not operate normally : Refer to

P.13B-286

,

diagnosis step for evaporative emission ventilation
solenoid trouble code DTC P0446.

AC002030 AB

HOSE G

EVAPORATIVE EMISSION

VENTILATION SOLENOID

AC002031AB

EVAPORATIVE EMISSION

VENTILATION SOLENOID

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-326

STEP 7. Pressure test for evaporator line from hose C to
hose P.
(1) Disconnect hose G from the evaporative emission

ventilation solenoid side, and plug the hoses from which the
hoses have been disconnected.

(2) Confirm that the evaporative emission system pressure

pump (Miller number 6872A) is operating properly. Perform
the self-test as described in the manufacturer's instructions.

(3) Connect an evaporative emission system pressure pump to

the fuel filler neck.

(4) Pressure test the system to determine whether any leaks

are present.

NOTE: "Pressure test" in this procedure refers to the I/
M240 Simulation Test (8 simple steps) described in the
evaporative emission system pressure pump (Miller number
6872A) manufacturer's instructions located in the lid of the
pump box.

Q: Are there any leaks in the evaporator line?

YES : Go to Step 8.
NO : Go to Step 20.

STEP 8. Pressure test for evaporator line from hose I to
hose P.
(1) Disconnect hose I from the evaporative emission canister

side, and plug the hose from which the pipes have been
disconnected.

(2) Perform the pressure test again.

Q: Is the pressure maintained inside the evaporator line?

YES : Go to Step 9.
NO : Go to Step 12.

AC002028 AB

HOSE G

AC000186

AC002036 AB

HOSE I

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-327

STEP 9. Check for leaks in the evaporator line hose C to
hose E.
(1) The leakage test with a hand vacuum pump on each hose

from hose C to hose E.

Q: Can the leaks be pinpointed?

YES : Replace that hose. Then go to Step 32.
NO : Go to Step 10.

STEP 10. Check for leaks in the evaporator line from hose
F to hose H.
(1) Remove the fuel tank. (Refer to GROUP 13C, Fuel

Tank

P.13C-6

.)

(2) The leakage test with a hand vacuum pump on each hose

from hose F to hose H.

Q: Can the leaks be pinpointed?

YES : Replace that hose, reinstall the fuel tank. Then go to

Step 32.

NO : Go to Step 11.

STEP 11. Check for leaks in the evaporative emission
canister.
(1) Connect a hand vacuum pump to the vent nipple of the

evaporative emission canister.

(2) Plug the other two nipples or loop a hose between the other

nipples.

(3) Apply a vacuum with the hand vacuum pump, and confirm

that the applied vacuum does not fluctuate.

Q: Does the vacuum pump gauge reading fluctuate?

YES : Replace the evaporative emission canister, and

reinstall the fuel tank. Then go to Step 32.

NO : Reinstall the fuel tank, then go to Step 32.

AC002074

HOSE C

AC

AC002284 AB

HOSE D

HOSE E

AC002037

HOSE F

HOSE H

AB

HOSE G

AC000191AB

VENT
NIPPLE

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-328

STEP 12. Check for leaks in the evaporator line hose I, L,
M, N and hose O.
(1) Remove the filler neck assembly. (Refer to GROUP 13C,

Fuel tank

P.13C-6

.)

(2) Sequentially apply vacuum with a hand vacuum pump

connected to hose I, L, M, N and hose O.

Q: Can the leaks be pinpointed?

YES : Replace that hose, reinstall the filler neck assembly.

Then go to Step 32.

NO : Go to Step 13.

STEP 13. Check the check valve A.
(1) Only when you blow the check valve from the direction

shown, it should pass air.

(2) When you blow the check valve, on air should leak from the

check valve body.

Q: Is there any failure?

YES : Replace it, reinstall the filler neck assembly. Then go

to Step 32.

NO : Go to Step 14.

STEP 14. Check the check valve B.
(1) When you blow the check valve from the arrow direction

shown above, it should pass more air.

(2) When you blow the check valve from the arrow direction

shown below, it should pass less air.

(3) When you blow the check valve, on air should leak from the

check valve body.

Q: Is there any failure?

YES : Replace it, reinstall the filler neck assembly and filler

neck protector. Then go to Step 32.

NO : Go to Step 15.

AC002032

AB

HOSE I

AB

AC002039

AB

AB

HOSE O

HOSE L

HOSE N

HOSE M

AC002076 AB

CHECK VALVE A

AC002078

CHECK VALVE B

AB