Mitsubishi Eclipse. Manual - part 248

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-485

STEP 12. 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, air should leak from the 

check valve body.

Q: Is the check valve A in good condition?

YES : Go to Step 13.
NO :  Replace the check valve A, reinstall the fuel tank and 

fuel filler neck assembly. (Refer to GROUP 13C, Fuel 
Tank 

P.13C-13

.) Then go to Step 18.

STEP 13. 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 the check valve B in good condition?

YES : Go to Step 14.
NO :  Replace the check valve B, reinstall the fuel tank and 

fuel filler neck assembly. (Refer to GROUP 13C, Fuel 
Tank 

P.13C-13

.) Then go to Step 18.

AC002039

CHECK VALVE A

AE

AC002076 AB

CHECK VALVE A

AC002039

CHECK VALVE B

AF

AC002078

CHECK VALVE B

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-486

STEP 14. Check for leaks in the evaporator line hose N.
(1) The leakage test with a hand vacuum pump on each hose 

from hose N.

Q: Is the hose in good condition?

YES : Go to Step 15.
NO :  Replace the hose, reinstall the fuel tank and fuel filler 

neck assembly. (Refer to GROUP 13C, Fuel Tank 

P.13C-13

.) Then go to Step 18.

STEP 15. Visually check for cracks in the fuel filler neck 
assembly.

Visually check for cracks in the fuel filler neck assembly.

Q: Is the fuel filler neck assembly in good condition?

YES : Go to Step 16.
NO :  Replace the fuel filler neck assembly, reinstall the fuel 

tank and fuel filler neck assembly. (Refer to GROUP 
13C, Fuel Tank 

P.13C-13

.) Then go to Step 18.

STEP 16. Check for leaks in the fuel tank.
(1) Visually check for cracks and leaks, etc.

NOTE: Carefully check the fuel pump assembly and the 
inner pressure sensor installation section in the fuel tank.

AC000195

HOSE N

AD

AC000196

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-487

(2) Connect an evaporative emission system pressure pump to 

the leveling valve nipple.

(3) Plug the filler hose, feed pipe, return pipe and rollover valve 

nipple connected to the fuel tank.
NOTE: If these items are not securely plugged here, the 
fuel could leak in the next step.

(4) Apply pressure with the evaporative emission system 

pressure pump.

(5) In the pressurized state, check for the leak by applying soap 

water, etc. to each section.

Q: Is the fuel tank in good condition?

YES : Go to Step 17.
NO :  Replace the fuel tank, reinstall the fuel tank and fuel 

filler neck assembly. (Refer to GROUP 13C, Fuel 
Tank 

P.13C-13

.) Then go to Step 18.

AC000197

AC000198

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-488

STEP 17. Using scan tool MB991958, check evaporative 
emission system monitor test.

CAUTION

• To prevent damage to scan tool MB991958, always turn 

the ignition switch to the "LOCK" (OFF) position before 
connecting or disconnecting scan tool MB991958.

• With this monitor, the ECM <M/T> or PCM <A/T> auto-

matically increases the engine speed to 1,600 r/min or 
more. Check that the transaxle is set to "neutral" <M/T> 
or "P" <A/T> position.

(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Erase the DTCs using scan tool MB991958.
(4) Check that the fuel cap is securely closed. (Tighten until 

three clicks are heard.)

(5) Start the engine.
(6) Select "System Test," and press the "YES" key.
(7) Select "Evap Leak Mon," and press the "YES" key.
(8) During the monitor, keep the accelerator pedal at the idling 

position.
NOTE: If the engine speed does not reach 2,000 r/min dur-
ing the monitor test, adjustment of the Speed Adjusting 
Screw may be needed. Refer to 

P.13A-928

. And adjust to 

the standard value.

(9) Keep the engine speed and engine load within the specified 

range. When the monitor test starts, the "In Progress" item 
on the scan tool MB991958 will change from "NO" to "YES."

(10)Turn the ignition switch to the "LOCK" (OFF) position. Then 

disconnect scan tool MB991958.

Q: What is displayed on scan tool MB991958?

"Evap Leak Mon. Completed. Test Passed" : The 

evaporative emission system is working properly at 
this time. Then go to Step 18.

"Evap Leak Mon. Completed. Test Failed and DTCs Set" 
: 

Replace the ECM <M/T> or PCM <A/T>. Then go to 
Step 18.

"Evap Lead Mon. discontinued. Retest again from the 
first" : The monitor was discontinued for a certain reason 

(vehicle speed input from ECM <M/T> or PCM <A/T>, 
engine speed and engine load deviating from 
specified range). Turn the ignition switch to the 
"LOCK" (OFF) position once, and recheck 
evaporative emission system monitor test.

AC303127

AB

MB991911

16-PIN

MB991827

MB991824