Main line pressure check
1. Preparation:
A) Warm up the transmission fluid to operating temperature (50 - 80°C).
b) Unscrew the plug and connect a pressure gauge in its place.
Attention: the pressure test should always be carried out by two people: one person should watch the wheels, and the second one should carry out the check.
2. Measure the pressure in the main line.
A) Chock the wheels of the vehicle and apply the parking brake.
b) Start the engine and check the idle speed.
V) Press the brake pedal and move the selector to the position "0". Measure pressure at idle.
G) Press the accelerator pedal all the way. Quickly measure line pressure when RPM reaches maximum. Compare the obtained pressure values with the values given in the table "Main line pressure".
Attention: release the accelerator pedal and stop the test if the rear wheels begin to rotate before the speed reaches the maximum value.
d) Repeat the test with the selector position in the range "R".
e) If the pressure is not as specified, check the adjustment of the throttle valve control cable and repeat the test.
3. Analysis of test results:
A) If on all ranges the pressure is higher than the specified values, then:
- throttle valve control cable not adjusted,
- throttle valve defective
- pressure regulator defective.
b) If in all ranges the pressure is below the specified values, then:
- Throttle control cable not adjusted.
- throttle valve defective
- faulty pressure regulator
- faulty automatic transmission pump,
- Faulty lock-up clutch of the increasing planetary gear set.
Table. Pressure in the main line, kPa
V) If the pressure is below the specified values in the range "D", That:
- there is a fluid leak in the control circuit on the range "D",
- Faulty forward clutch.
G) If the pressure is below the specified values in the range "R", That:
- there is an automatic transmission fluid leak in the control circuit on the range "R",
- defective reverse clutch
- the brake of the first gear and reverse gear is faulty.
Checking Speed Regulator Pressure (A140L)
1. Warm up the automatic transmission to operating temperature (50 - 80°C).
2. Jack up the car.
3. Unscrew the plug of the channel of the high-speed regulator and install a pressure gauge in its place.
Note:
- Check throttle cable adjustment.
- Check tire pressure.
4. The parking brake must be loose.
5. Start the engine.
6. Set the selector to position "D" and measure the speed regulator pressure as indicated in the table.
If the pressure does not correspond to the specified values, then either the working fluid leaks in the speed regulator circuit, or the speed regulator itself is faulty.