Symptoms - Automatic Transmission. Chevrolet Epica 2004

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2004 🢒 Epica 🢒 Transmission/Transaxle 🢒 Automatic Transmission - ZF 4HP 16 🢒 Symptoms - Automatic Transmission

Table 1:	Transaxle Oil Leakage
Table 2:	Transaxle Oil Leakage
Table 3:	Shift Quality
Table 4:	Malfunction

Oil Leakage

Important: Careful localization of leakage points may make it possible to prevent incorrect or cost-intensive repairs.

•	Thoroughly clean the transaxle, engine, and surrounding area using a steam jet, for example.

•	To locate leakage, use a suitable identifying spray or similar product.

•	Depending on the amount of leakage, take the car for a short or a longer test drive - It may prove sufficient to place the car on a hoist and run the engine at idle speed to trace the leak.

•	If possible, determine exactly which type of oil is escaping.

Transaxle Oil Leakage

Condition

Action

Oil Pump-Torque Converter Sealing

•	Visually inspect the torque converter sealing.

•	Replace the converter sealing.

Crankshaft Sealing Ring

•	Verify if the engine oil or transmission fluid is leaking.

•	If the leak is engine oil, replace the sealing ring.

Torque Converter

•	Visually inspect the torque converter.

•	Fit an exchange converter.

Oil Content Too High

•	Verify the oil level, TFT and axle oil

Important: Comply with the measuring procedure. Refer to Transmission Fluid Level Inspection .

•	Inspect the oil level at the overflow plug and adjust to the proper level if necessary.

•	Correct the oil level and check after a test drive.

O-ring at Bolt Head Damaged or Missing

•	Inspect the O-ring.

•	Replace the O-ring.

Shaft Seal

•	Visually inspect the shaft seal.

•	Replace the sealing ring.

Hose Clamp Loose

•	Inspect that the hose clamp fits tightly.

•	If necessary, tighten the clamp.

Oil Pan Gasket Not Installed Properly

•	Verify that the gasket was positioned properly.

•	Install the gasket properly.

Oil Pan Gasket Damaged

•	Visually inspect the gasket.

•	Replace the gasket.

Bolt at Bracket Loose

Verify the torque of the bracket bolt. Tighten the bolt, if necessary.

Sealing Ring at Oil Dipstick

•	Inspect the O-ring

•	If necessary, replace the O-ring.

Sealing Ring Near End-Cover Connection Defective

•	Inspect the sealing rings.

•	Put in a new sealing ring.

•	Inspect the O-ring.

Sealing Ring Selector Shaft

•	Inspect the sealing ring.

•	Replace the sealing ring.

O-Ring at Socket Outlet

•	Inspect the O-ring.

•	Replace the O-ring.

O-Ring and Speed Sensor Connection

•	Inspect the O-ring.

•	Replace the O-ring.

Oil Leak Incorrectly Identified

No oil leak is possible at this point.

Speed Sensor Itself Is Leaking

•	Inspect the speed sensor.

•	Replace the speed sensor.

Hair Line Crack at the Piping in the Connection Area, Sealing Ring Fit in Transaxle Housing

•	Pressurize the line with compressed air.

•	Replace the lines.

O-ring Defective, Incorrect

•	Inspect the O-ring.

•	Replace the O-rings.

Plug Loose

Verify the torque for the screw plug.

Noise

Transaxle Oil Leakage

Condition

Action

Transmission Fluid Temperature (TFT) Level Too Low

•	When the TFT level is too low, the gear wheels from the transaxle oil pump might generate noise.

•	Inspect the TFT level fill to proper level, if necessary.

Monolith in Catalytic Converter Has Broken

•	Inspect the exhaust by shaking the catalytic converter casing.

•	Replace the catalytic converter if necessary.

Noise From Auxiliaries - E.G. Exhaust System, Alternator, Drive Shafts

Inspect the following components to eliminate the faults:

•	The exhaust system

•	The alternator

•	The drive shafts

Noise From Tires Or Wheel Bearings

Eliminate the fault if necessary.

Noise From Planetary Gears

Whistling noise on the traction and overrun in 1st gear only caused by high rotating speeds functionally unavoidable

Cumulative Tooth Backlash In The Complete Drive Line

Production status - Explain to the customer.

Jerky Noise Of The Parking Lock - E.G. When The Car Is Standing On A Gradient

•	Load reversal reaction.

•	Apply the hand brake before selecting the parking lock (position P).

The Engine's Torsional Vibrations Are Being Transmitted To The Drive Shafts

•	At low speeds in 4th gear, vibration can arise, driving at too low an engine speed.

•	Noise is functionally unavoidable due to tolerances. Explain it to the customer.

Torque Reaction Strut Loose

Inspect the mounting and repair if necessary.

Shift Quality

Important:

•	The assessment of shift quality is, to a large extent, an individual, subjective matter. Take careful note of how the customer describes the complaint and the manner in which he or she handles the vehicle and the controls.

•	A sudden deterioration of shift quality may also be cause by the transaxle selection an emergency or substitute program.

•	Carry out the general checks described in the automatic transaxle diagnostic information.

•	Perform a test drive to answer the following questions.

-	In which driving situation does the shift quality complaint arise?

-	To which shifts does the complaint apply?

-	Is the complaint reproducible within a short period or has it only occurred sporadically or on a single occasion?

•	Check the oil level and oil quality.

•	Interrogate the fault memory and read out measurement block data.

Shift Quality

Condition

Action

Rapid Pressure Build-up in the Clutch

Operating error position selected several times in quick succession.

Jerk When Parking Lock is Released

Refer to Noise Symptom table.

Incorrect Electronic Transaxle Control Module

Inspect the data status for transaxle control module.

Accelerator Pedal in Indefinite Position Between Full Throttle and Kick Down

•	Ask the customer if the problem occurs during kick down or full throttle.

•	Inspect the setting according to engine repair instruction. Adjust if necessary.

Control Overlap Between to Clutches During Shift

•	Production Status

•	Explain to the customer.

Temperature Sensor - Not Fault Memory

Inspect the function according to the Drive Range 4th gea, Emergency/Substitute Mode or Drive Range 3rd gear, Emergency/Substitute Mode.

Kick Down Setting Incorrect

•	Inspect if the floor mat is obstructing the accelerator pedal.

•	Inspect the kick down for proper operation.

Malfunction

Important: The faults dealt with here concern the transaxle functions such as traction, forward and reverse, and all types of shifts. Entries will not always be made in the fault memory.

Perform the general inspections according to the automatic transaxle diagnostic procedure.

•	Test drive the vehicle.

•	Inspect the oil level quality.

•	Interrogate the fault memory.

Malfunction

Condition

Action

Vehicle will not move or shift, even with the TCM disconnected.

•	This is usually due to too little oil being added or internal damage.

•	A repair is not possible. Exchange the transaxle if necessary.

Kick Down Switch Not Functioning Properly

For checking and remedial action, refer to Drive Range - Third Gear, Emergency/Substitute Mode or Drive Range - Fourth Gear, Emergency/Substitute Mode .

Vehicle Is in Emergency Mode

For checking and remedial action, refer to Drive Range - Third Gear, Emergency/Substitute Mode or Drive Range - Fourth Gear, Emergency/Substitute Mode .