NO.14 ENGINE FLARES UP OR SLIPS WHEN UPSHIFTING OR DOWNSHIFTING [SJ6A-EL]

id050307801900

14

Engine flares up or slips when upshifting or downshifting

DESCRIPTION

•  When the accelerator pedal is depressed for acceleration from standstill, engine speed increases but the vehicle speed increases slowly.

•  When the accelerator pedal is depressed while driving, engine speed increases but the vehicle speed does not.

POSSIBLE CAUSE

•  There is clutch slippage because the clutch is stuck or the line pressure is low.

―  Clutch stuck, slippage (C1 clutch, C2 clutch, C3 clutch, B1 brake, B2 brake, B3 brake)

•  Line pressure low

•  Incorrect throttle position signal

•  Incorrect accelerator pedal position signal

•  Incorrect engine speed signal

•  Incorrect engine coolant temperature signal

•  Incorrect engine torque signal

•  VSS malfunction

•  Turbine sensor malfunction

•  Sensor GND malfunction

•  Shift solenoid A malfunction

•  Shift solenoid B malfunction

•  Shift solenoid C malfunction

•  Shift solenoid D malfunction

•  Shift solenoid E malfunction

•  Line pressure control solenoid malfunction

•  TCC control solenoid malfunction

•  Shift solenoid F malfunction

•  Shift solenoid G malfunction

•  Body GND malfunction

•  Control valve body malfunction

Note

•  Before following the troubleshooting steps, make sure that the Automatic Transmission On-Board Diagnostic and Automatic Transmission Basic Inspection are conducted. (See BASIC INSPECTION [SJ6A-EL].)

Diagnostic procedure

STEP	INSPECTION		ACTION
1	• Is the line pressure normal? (See MECHANICAL SYSTEM TEST [SJ6A-EL].)	Yes	Go to the next step.
1		No	Repair or replace any malfunctioning parts according to the inspection results.
2	• Is shift point normal? (See ROAD TEST [SJ6A-EL].)	Yes	Go to the next step.
2	• Is shift point normal? (See ROAD TEST [SJ6A-EL].)	No	Go to No.9 “ABNORMAL SHIFTING”.
3	• Access the following PCM PIDs using the M-MDS. ― RPM ― APP ― TP ― ECT • Are PIDs value normal?	Yes	Go to the next step.
3		No	Inspect and repair suspected PID related part.
4	• Stop the engine. • Inspect following solenoids. (See SOLENOID VALVE INSPECTION [SJ6A-EL].) ― Shift solenoid A ― Shift solenoid B ― Shift solenoid C ― Shift solenoid D ― Shift solenoid E ― Line pressure control solenoid ― TCC control solenoid ― Shift solenoid F ― Shift solenoid G • Are they normal?	Yes	Inspect the ATF condition. • If large amount of metal specks are found, overhaul the transaxle and repair or replace any malfunctioning parts. (See Automatic Transmission Workshop Manual SJ6A-EL.) • If a large amount of metal specks are not found, replace the control valve body. (See CONTROL VALVE BODY REMOVAL [SJ6A-EL].) (See CONTROL VALVE BODY INSTALLATION [SJ6A-EL].)
4		No	Replace suspected solenoid. (See Automatic Transmission Workshop Manual SJ6A-EL.)
5	• Inspect the coupler component for open or short. • Are coupler component normal?	Yes	Go to the next step.
5		No	Replace the coupler component.
6	• Inspect the ATF condition. • Are a large amount of specks found?	Yes	Replace the transmission. (See AUTOMATIC TRANSMISSION REMOVAL/INSTALLATION [SJ6A-EL].)
6		No	Replace the control valve body. (See CONTROL VALVE BODY REMOVAL [SJ6A-EL].) (See CONTROL VALVE BODY INSTALLATION [SJ6A-EL].)
7	• Verify test results. ― If normal, return to the diagnostic index to service any additional symptoms. ― If malfunction remains, inspect the related Service Information and perform repair or diagnosis. • If the vehicle is repaired, troubleshooting completed. • If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM.