Symptom Diagnosis. Pontiac Grand Prix 1999

For 1990-2009 cars only

Makes 🢒 Pontiac 🢒 1999 🢒 Grand Prix 🢒 Engine 🢒 Engine Controls - 3.8L 🢒 Symptom Diagnosis

Symptom Diagnosis (1999 W Pontiac / 4T65-E)

Diagnostic Category

Diagnostic Information

This table consists of seven diagnostic categories that are located in the left-hand column. Using this column, choose the appropriate category based on the operating conditions of the vehicle or transmission. After selecting a category, use the right-hand column to locate the specific symptom diagnostic information.

Important: The Functional Test Procedure should be performed before beginning any diagnosis. If this procedure has not already been performed, refer to Functional Test .

Fluid Diagnosis

This category contains the following topics:

•	Fluid condition (appearance, contaminants, smell, overheating)

•	Line pressure (high or low)

•	Fluid leaks

•	Refer to Transmission Fluid Check .

•	Refer to Incorrect Line Pressure .

•	Refer to Transmission Component Fluid Leak Diagnosis .

•	Refer to Fluid Leak Diagnosis .

Noise and Vibration Diagnosis

This category contains the following topics:

•	Torque converter diagnosis

•	Noise and vibration analysis

•	Refer to Flexplate/Torque Converter Vibration Test .

•	Refer to Noise and Vibration Analysis .

Range Performance Diagnosis

This category contains the following topics:

•

No Park

•	No Reverse or slips

•	No Drive or slips

•	No engine braking

•	Refer to No Park Range .

•	Refer to Slips in Reverse or No Reverse .

•	Refer to Slips in Drive or No Drive .

•	Refer to Locked Up in Drive/Reverse .

•	Refer to No Engine Braking in Manual Second or Low Range .

Shift Quality (Feel) Diagnosis

This category contains the following topics:

•	Harsh shifts

•	Soft shifts

•	Harsh engagement (garage shifts)

•	Delayed engagement (garage shifts)

•	Refer to Harsh or Soft 1-2 Shift Feel .

•	Refer to Harsh or Soft 2-3/3-2 Shift Feel .

•	Refer to Harsh or Soft 3-4/4-3 Shift Feel .

•	Refer to Harsh Park to Reverse/Drive Engagement .

•	Refer to Delayed Park to Reverse/Drive Engagement .

Shift Pattern

This category contains the following topics:

•	No upshift

•	Slipping or missing gears

•	One forward gear only

•	Two forward gears only

•	Non-First gear start

•	Refer to Slipping or No First Gear .

•	Refer to Slipping or No Second Gear .

•	Refer to Slipping or No Third Gear .

•	Refer to Slipping or No Fourth Gear .

•	Refer to First Gear Only .

•	Refer to Second Gear Only .

•	Refer to Third Gear Only .

•	Refer to Fourth Gear Only .

•	Refer to First and Second Gear Only - 2-3 Solenoid Stuck On .

•	Refer to First and Fourth Gear Only - 1-2 Solenoid Stuck On .

•	Refer to Second and Third Gear Only (1-2 Solenoid Stuck Off) .

•	Refer to Third and Fourth Gear Only (2-3 Solenoid Stuck Off) .

Shift Speed Diagnosis

This category contains the following topic:

Incorrect shift points

Refer to High or Low Upshift or Downshift Speed .

Torque Converter Diagnosis

This category contains the following topics:

•	Torque converter diagnosis

•	TCC does not apply

•	TCC does not release

•	TCC shudder

•	Refer to Torque Converter Diagnosis .

•	Refer to No Torque Converter Clutch Apply .

•	Refer to Converter Clutch Stuck On in All Gears .

•	Refer to Converter Clutch Stuck On in Second, Third and Fourth Gear .

•	Refer to Harsh Torque Converter Clutch Apply or Release .

•	Refer to Converter Clutch Apply Rough, Slips, or Shudders .