Inspection Procedure 13

Inspection procedure 13: The engine stalls decelerating

COMMENT

- The abnormal air/fuel ratio or other similar defects can possibly be caused by the insufficient intake air volume.

TROUBLESHOOTING HINTS (The most likely causes for this case:)

- Malfunction of the ignition system.
- Dirtiness around throttle valve.
- Malfunction of the ECM.

DIAGNOSIS

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code (DTC).





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.

(1)Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Read the DTC.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is any DTC set?

YES Refer to Diagnostic Trouble Code Chart Multiport Fuel Injection (MFI).

NO Go to Step 2.

STEP 2. Inspection of throttle body (throttle valve area) for dirtiness.

Q. Is the throttle valve area dirty?

YES Refer to Throttle Body (Throttle Valve Area) Cleaning Throttle Body Cleaning.
NO Go to Step 3.
STEP 3. Using scan tool MB991958, check data list.

(1)Turn the ignition switch to the "ON" position.

(2)Check the following items in the data list. Refer to Data List Reference Table Data List Reference Table.
1. Item 11: Accelerator Pedal Position Sensor (main).

2. Item 12: Accelerator Pedal Position Sensor (sub).

3. Item 13: Throttle Position Sensor (main).

4. Item 15: Throttle Position Sensor (sub).

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

Q. Are they operating properly?

YES Go to Step 4.
NO Repair or replace it. Then confirm that the malfunction symptom is eliminated.
STEP 4. Check the spark plugs.

Procedures.

Q. Are there any abnormalities?

YES Replace the spark plug. Then confirm that the malfunction symptom is eliminated.
NO Check the ignition coil Testing and Inspection). Then confirm that the malfunction symptom is eliminated.