MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.0L>
13B-566
STEP 3. Using scan tool MB991502, check data list.
CAUTION
To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check the following items in the data list. Refer to, Data List
Reference Table
a. Item 21: Engine Coolant Temperature Sensor.
b. Item 28: A/C Switch.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Are they operating properly?
YES :
Go to Step 4.
NO :
Repair or replace. Then confirm that the malfunction
symptom is eliminated.
STEP 4. Adjust the basic idle speed.
Refer to, Basic Idle Speed Adjustment for the adjustment pro-
cedure
.
Standard value: 700
±
50 r/min
Q: Is the Idle speed normal?
YES :
Refer to, Clean the throttle valve area
NO :
The check is completed.
INSPECTION PROCEDURE 10: Idle Speed Is Low (Improper Idle Speed).
.
COMMENT
•
In cases such as the above, the cause is proba-
bly that the intake air volume during idle is too
small.
.
TROUBLESHOOTING HINTS (The most likely
causes for this case:)
•
Malfunction of the IAC system.
•
Malfunction of the throttle body.
DIAGNOSIS
Required Special Tool:
•
MB991502: Scan Tool (MUT-II)
AKX01177
16 PIN
MB991502
AB