Inspection Procedure 13
COMMENTIf acceleration is poor when downshifting occurs while driving, a malfunction of the engine system or a brake or clutch may exist.
TROUBLESHOOTING HINTS
The most likely causes for this case:
- Malfunction of the engine system
- Malfunction of the clutch system and brake system
- Malfunction of the PCM
DIAGNOSIS
STEP 1. Check The Engine System.
Refer to <2.4L Engine>, Diagnosis - Symptom Chart - Poor acceleration or <3.0L Engine>, Diagnosis - Symptom Chart - Poor acceleration. If the inspection result is not good, diagnose, repair, and/or replace the engine component(s). If the inspection result is good, go to Step 2.
STEP 2. Perform The Torque Converter Stall Test.
Perform the torque converter stall test. Refer to Torque Converter Stall Test. Converter Stall Speed TestThen check for the symptom. If the symptom is eliminated, diagnosis is complete. If the symptom is not eliminated, go to Step 3.
STEP 3. Perform The Hydraulic Pressure Test.
Perform the hydraulic pressure test. Hydraulic Pressure Tests Refer to Hydraulic Pressure Test. Hydraulic Pressure Tests Then check for the symptom. If the symptom is eliminated, diagnosis is complete. If the symptom is not eliminated, go to Step 4.
STEP 4. Check Each Brake System And Clutch System.
1. Remove the valve body cover and valve body.
2. Blow compressed air into the each brake oil orifice and clutch oil orifice of the transaxle case, and check if the each brake and clutch piston move and air pressure is maintained.
If the air pressure is maintained, diagnosis is complete.
If the air pressure is not maintained, go to Step 5.
STEP 5. Check Each Brake System And Clutch System.
Remove the transaxle.
Check the facings for seizure and piston seal ring for damage and interference with retainer. Repair or replace the faulty parts. Refer to Underdrive Clutch, Input Shaft, Reverse and Overdrive Clutch. Then check for the symptom.
If the symptom is eliminated, diagnosis is compete.
If the symptom is not eliminated, go to Step 6.
STEP 6. Replace The PCM.
Replace the PCM. The immobilizer-ECU and the ignition key should be replaced together with it. Refer to Ignition Switch and Immobilizer System - Ignition Switch and Immobilizer System. Confirm that the malfunction symptom is eliminated.
If malfunction is eliminated, diagnosis is complete.