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1999 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1038Torque1596Fluid17DTC3336Battery2Maintenance0Recalls5
P0943high severityPowertrain

Hydraulic Pressure Unit Cycling Period Too Short

on 1999 Toyota Tacoma 2.7L I4 · RWD

What this code means

The transmission hydraulic pressure accumulator is cycling on and off too frequently. This often points to a leak in the hydraulic system or a failing pump that can't hold pressure.

Symptoms

  • Harsh or erratic shifting
  • Transmission warning light on
  • Whining noise from transmission

Common causes

  • Internal transmission fluid leak
  • Faulty hydraulic pump
  • Worn accumulator or seals
  • Low transmission fluid level

Diagnostic steps

  1. Check transmission fluid level and condition
  2. Scan for related transmission codes
  3. Test hydraulic system pressure
  4. Inspect pump and accumulator for wear or leaks
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