No.8 Low Maximum Speed And Poor Acceleration: Notes

WARNING: This page is about a different car, the 2005 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.

LOW MAXIMUM SPEED AND POOR ACCELERATION DESCRIPTION AND POSSIBLE CAUSE

8	Low maximum speed and poor acceleration
DESCRIPTION	Vehicle acceleration is poor at start. Delayed acceleration when accelerator pedal is depressed while driving.
POSSIBLE CAUSE	Engine malfunction Clogged air cleaner, inaccurate ignition tinning, ignition leak, reduced compression, incorrect engine torque signal, etc. AT malfunction Transmission fixed in 3GR (operating fail-safe function) Input/output signal malfunction (VSS, turbine sensor, TFT sensor, pressure control solenoid, TCC solenoid, shift solenoids A, B, C and F) Maximum speed is low or acceleration is poor because 3GR is fixed as a fail-safe. In such cases, DTC is stored. Improper TCM ground Transmission is mechanically fixed in 3GR if TCM stops operating due to improper TCM ground. In such cases, DTC is stored. Improper ground of GND return circuit at AT If there is improper ground of GND return circuit, clutch pressure may decrease, causing clutch slippage. Improper adjustment TR switch Incorrect characteristic of accelerator position sensor, accelerator position signal, TP sensor, or throttle opening angle signal (CAN communication) TP sensor and throttle opening angle signal (CAN communication) do not change in proportion to throttle opening angle. Due to this, high or low gear is fixed, resulting in low maximum speed and poor acceleration. (Refer to improper accelerator position sensor, accelerator position signal, TP sensor, throttle opening angle signal (CAN communication) in "NO.11 ABNORMAL SHIFTING ".) Clutch slippage (low clutch and high clutch) In the event of clutch slippage, a DTC (incorrect gear ratio) is stored. Reduced line pressure Control valve body malfunction (improper operation, stuck, clogged oil passage) Hydraulic circuit clogging (Shift solenoid A, B, C and F, and TCC solenoid) Control valve spool malfunction No torque generated. Torque converter malfunction (improper operation) 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 .)

Low maximum speed and poor acceleration

DESCRIPTION

Vehicle acceleration is poor at start.
Delayed acceleration when accelerator pedal is depressed while driving.

POSSIBLE CAUSE

Engine malfunction
- Clogged air cleaner, inaccurate ignition tinning, ignition leak, reduced compression, incorrect engine torque signal, etc.
AT malfunction
- Transmission fixed in 3GR (operating fail-safe function)
- Input/output signal malfunction (VSS, turbine sensor, TFT sensor, pressure control solenoid, TCC solenoid, shift solenoids A, B, C and F)
  - Maximum speed is low or acceleration is poor because 3GR is fixed as a fail-safe. In such cases, DTC is stored.
- Improper TCM ground
  - Transmission is mechanically fixed in 3GR if TCM stops operating due to improper TCM ground. In such cases, DTC is stored.
- Improper ground of GND return circuit at AT
  - If there is improper ground of GND return circuit, clutch pressure may decrease, causing clutch slippage.
- Improper adjustment TR switch
- Incorrect characteristic of accelerator position sensor, accelerator position signal, TP sensor, or throttle opening angle signal (CAN communication)
  - TP sensor and throttle opening angle signal (CAN communication) do not change in proportion to throttle opening angle. Due to this, high or low gear is fixed, resulting in low maximum speed and poor acceleration. (Refer to improper accelerator position sensor, accelerator position signal, TP sensor, throttle opening angle signal (CAN communication) in "NO.11 ABNORMAL SHIFTING ".)
- Clutch slippage (low clutch and high clutch)
  - In the event of clutch slippage, a DTC (incorrect gear ratio) is stored.
- Reduced line pressure
- Control valve body malfunction (improper operation, stuck, clogged oil passage)
  - Hydraulic circuit clogging (Shift solenoid A, B, C and F, and TCC solenoid)
  - Control valve spool malfunction
- No torque generated.
  - Torque converter malfunction (improper operation)
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 .)