Inspection Procedure 11: The Feeling of Impact or Vibration when Accelerating

COMMENTS ON TROUBLE SYMPTOM

The failure could possibly be caused by the ignition leak occurring in association with the increase in the voltage required by the spark plug during the acceleration, failed electronic-controlled throttle valve system and so on.

PROBABLE CAUSES

Failed ignition system
Failed electronic-controlled throttle valve system
Contamination around the throttle valve
Failed CVT
Failed engine-ECU

DIAGNOSIS PROCEDURE

note

To protect the CVT, the CVT-ECU outputs, into the engine-ECU, the request signal to reduce the engine torque according to the operation condition, Based on the signal, the engine-ECU closes the throttle valve, retards the ignition or carries out fuel cut. At that time, the engine output seems to temporarily reduce, but there is no malfunction.

STEP 1. M.U.T.-III diagnosis code

Q. Is diagnosis code set?

	Inspection chart for diagnosis code (Refer to ).

	NO : Go to Step 2.

STEP 2. M.U.T.-III diagnosis code

note

When the CVT has a malfunction, the CVT-ECU might output the request signal of reducing the engine torque in order to protect the CVT.

Confirm the diagnosis code is set from CVT-ECU.

Q. Is the diagnosis code set?

	Perform troubleshooting of CVT System (Refer to GROUP 23A - Diagnosis Code Chart ).

	Go to Step 3.

STEP 3. M.U.T.-III data list

Data list reference table (Refer to ).

Item 11: Accelerator pedal position sensor (main)
Item 12: Accelerator pedal position sensor (sub)
Item 13: Throttle position sensor (main)
Item 15: Throttle position sensor (sub)

Q. Are the check results normal?

	Go to Step 4.

	Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value. Inspection chart for diagnosis code (Refer to ).

STEP 4. Check throttle body (throttle valve portion) contamination.

Q. Is the check result normal?

	Go to Step 5.

	Throttle body (throttle valve area) cleaning (Refer to ).

STEP 5. Visual check of ignition spark.

Remove the spark plug and install it to the ignition coil.
Connect the ignition coil connector.
Disconnect all injector connectors.
At the engine start, check each spark plug produces a spark.

Q. Is the check result normal?

	Replace the engine-ECU.

	Check Inspection Procedure - ignition circuit system (Refer to ).