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Excessive Shock or Flares On 1-2 Upshift or 2-1 Downshift




Excessive shock or flares on 1-2 upshift or 2-1 downshift

Diagnostic Procedure:

1. A/T clutch pressure control solenoid valve A defective

2. A/T clutch pressure control solenoid valve C defective

3. 2nd clutch transmission fluid pressure switch defective

4. CPC valve A defective

5. CPC valve C defective

6. Foreign material in separator plate orifice

7. 2nd accumulator defective

8. 2nd check ball stuck

9. 2nd clutch defective

Also check for:

- Check for a stored DTC, and check for loose connectors.
- Inspect the A/T clutch pressure control solenoid valve body gasket and the ATF feed pipes for wear and damage. If the A/T clutch pressure control solenoid valve is stuck, inspect the CPC valves.
- Check for a clogged orifice in the transmission fluid pressure switch connector. If the orifice is clogged, remove it and clean the connector.
- Check the 1st and 2nd clutch pressures.
- Inspect the clutch piston, the clutch piston check valve, and the O-rings. Check the spring retainer for wear and damage. Inspect the clearance between the clutch end-plate and the top disc. If the clearance is out of tolerance, inspect the clutch discs and the plates for wear and damage, and inspect the clutch wave-plate height. If the discs and the flat-plates are worn or damaged, replace the discs and the flat-plates as a set. If the wave-plate height is out of tolerance, replace the wave-plate. If the discs and the plates are OK, adjust the clearance with the clutch end-plate.