Inspection Procedure 10: Poor acceleration

COMMENTS ON TROUBLE SYMPTOM

During driving, if the acceleration is not performed even when downshifted, the cause is probably a malfunction of the engine system, line pressure control solenoid system, valve body, or oil pump.

PROBABLE CAUSES

Malfunction of engine system
Malfunction of valve body (line pressure control solenoid)
Malfunction of the A/T-ECU
A/T internal error (oil pump, clutches, brakes, etc.)

DIAGNOSIS PROCEDURE

STEP 1. Engine system check

Refer to GROUP 13B - Troubleshooting

<6B3>.

Refer to GROUP 13C - Troubleshooting

<4N1>.

Q. Is the check result normal?

	Go to Step 2.

	Repair the engine system.

STEP 2. Retest the system

If the trouble symptom is not solved, replace the valve body. Then, check the trouble symptom again.

Q. Is the trouble symptom reproduced?

	Go to Step 3.

	This diagnosis is complete.

STEP 3. A/T-ECU replacement

(1)Replace the A/T-ECU.

(2)Test drive the vehicle.

(3)Verify that the condition described by the customer exists.

Q. Is the trouble symptom reproduced?

	After checking the oil pump for damage, check each clutch and brake for any damage, and replace if necessary.

	This diagnosis is complete.