Checking the position of the factory adjustment screw
Do not touch the factory adjustment screw «Fixed SAS» on the throttle body, the position of which is adjusted with high accuracy at the factory.
In the event that the factory adjustment of the screw was mistakenly violated «Fixed SAS», the fully closed throttle position will be changed (idle position). As a result, the engine and CVT electronic control unit will be retrained to the wrong throttle position.
Engine 4G15.
Engine 4G93.
Cleaning the throttle body
1. Start the engine, warm it up to a coolant temperature of 80°C or higher, and then stop the engine.
2. Disconnect the air hose from the throttle body.
3. Spray the recommended washer cleaner inside the throttle body through the intake port and wait about 5 minutes.
Detergent cleaner - Three bond 6601
4. Start the engine. Press the accelerator pedal several times and let the engine run at idle speed for 1 minute.
5. If deposits in the throttle body are not removed, then repeat the steps "3" And "4".
6. Connect the air hose to the throttle body.
7. Delete codes of malfunctions from memory of the electronic control unit of the engine and a variator.
Throttle position sensor adjustment
1. With the ignition off, connect the tester to the diagnostic socket.
2. If the tester is not available, then perform the following operations:
A) Disconnect the throttle position sensor connector and connect the test harness between the connectors.
Engine 4G15.
Engine 4G93.
b) With wire connector "crocodile" connect a voltmeter across the terminal "2" (sensor signal for channel #1) or "4" (sensor signal for channel #2) and conclusion "3" ("weight" sensor) sensor connector.
3. Disconnect the throttle servo connector.
4. Turn on the ignition (do not start the engine).
5. Throttle position sensor adjustment (channel #1).
A) Manually fully close the throttle and measure throttle position sensor signal voltage (channel #1).
Rated voltage - 0.4 -0.6V
b) If the measured value does not correspond to the nominal value, then loosen the throttle position sensor mounting bolts. Rotate the sensor housing to adjust the sensor signal voltage.
Engine 4G15.
Engine 4G93.
6. Throttle position sensor adjustment (channel #2).
A) Manually fully close the throttle and measure throttle position sensor signal voltage (channel #2).
Rated voltage - 4.2 - 4.8 V
b) If the voltage is not correct, replace the throttle position sensor.
7. Turn off the ignition.
8. If the test was performed without a tester, then remove the test lead harness and voltmeter.
9. Connect the throttle servo connector.
10. Delete codes of malfunctions from memory of the electronic control unit of the engine.
11. Perform throttle servo relearn.
Turn the ignition key from position "OFF" (OFF) into position "ON" (ON), then turn the key to position "OFF" (OFF) and wait 10 seconds.
12. Disconnect the tester.
Accelerator pedal position sensor adjustment
Attention: do not touch the accelerator pedal position sensor unless absolutely necessary, the position of which is adjusted with high accuracy at the factory. Adjustment should only be performed if the factory setting of the sensor has been violated by mistake.
1. With the ignition off, connect the tester to the diagnostic socket.
2. If the tester is not available, then perform the following operations.
A) Disconnect the accelerator pedal position sensor connector and connect the test harness between the connectors.
b) With wire connector "crocodile" connect a voltmeter to the output "3" (sensor signal for channel #1) and conclusion "1" (''weight" sensor for channel #1).
3. Adjusting the accelerator pedal position sensor.
A) Slightly loosen the screws securing the accelerator pedal position sensor.
b) Hold the accelerator pedal in the position where it touches the stopper.
4. Turn on the ignition (do not start the engine).
5. Turn the sensor around the control pin, and adjust the signal voltage of the accelerator pedal position sensor so that it corresponds to the nominal value.
Rated value - 0.985 - 1.085 V
6. Tighten the screws securing the accelerator pedal position sensor.
Checking the fuel pressure in the line between the injection pump and the low pressure pump
1. To prevent fuel splashing, bleed residual pressure from the high pressure line (see relevant subsection).
2. Disconnect the high pressure fuel hose from the injection pump as shown in the figure.
Attention: since there is residual pressure in the fuel line, cover the hose connection with a rag to prevent fuel splashing.
Engine 4G15.
Engine 4G93.
3. Install special devices for measuring pressure.
A) Prepare adapter (tee) for connection to the injection pump.
b) Connect the adapter between the high pressure fuel hose and the injection pump.
V) Install a pressure gauge or pressure transducer on the adapter. When doing this, be sure to install suitable O-rings to prevent fuel leaks.
G) (Checking pressure with a sensor) Connect the power wire of the pressure sensor to the power supply (cigarette lighter), and the signal wire to the tester.
4. Check for leaks after installing the pressure gauge.
A) Connect the tester to the diagnostic socket.
Attention: you can disconnect or connect the tester only when the ignition is off.
b) Turn on the ignition (do not start the engine).
V) Select sub-item No. 07 of item "ACTUATOR TEST" tester and activate the low pressure fuel pump in the tank. Check for fuel leaks at the connections.
G) Complete the paragraph "ACTUATOR TEST" tester and turn off the ignition.
5. Checking the pressure with the fuel pump on (low pressure).
A) Start the engine and leave it to idle.
b) When the engine is idling, measure the fuel pressure in the line.
Rated value - 324 kPa
V) Check that the fuel pressure at idle does not drop even after a few applications of the accelerator pedal (to increase the engine speed).
G) If any of the pressure test results are abnormal, then troubleshoot and correct them according to the table "Results of checking the fuel pressure in the low pressure line with the fuel tank pump on".
6. Checking the drop in fuel pressure after turning off the fuel pump.
A) Stop the engine (turn off the fuel pump) and check for changes in the fuel pressure gauge reading. The fuel system is OK if the pressure in the fuel line does not decrease within 2 minutes. If the pressure drops, then determine the rate of pressure drop (gradually/instantly) and troubleshoot and correct them.
b) If the fuel pressure drops gradually after stopping the engine, then there are leaks through the fuel pressure regulator valve (loose valve seat).
V) If, after stopping the engine, the fuel pressure drops immediately, the check valve in the fuel pump remains open all the time (replace fuel pump).
7. To prevent splashing of fuel, bleed residual pressure from the high pressure line.
8. Disconnect special adaptations in gathering from TNVD and a fuel hose.
Attention: since there is residual pressure in the fuel line, cover the hose connection with a rag to prevent fuel splashing.
9. Replace the O-ring on the high pressure fuel hose flange with a new one, lubricate the O-ring with engine oil before installation.
10. Connect a fuel hose to TNVD and tighten a fastening bolt the nominal moment.
11. Check for fuel leaks in the same way as in paragraph "4".
12. Disconnect the tester.
Checking the fuel pressure in the line between the injection pump and the injectors
Note: pressure measurement in the high pressure line (between injection pump and injectors) should be carried out only after making sure that the fuel pressure between the low pressure pump in the tank and the injection pump is correct.
1. With the ignition off, connect the tester to the diagnostic socket.
2. Disconnect the intermediate connector of the injectors.
Engine 4G15.
Engine 4G93.
Table. The results of checking the fuel pressure in the low pressure line with the fuel pump in the tank turned on.
3. Turn the ignition key to position "ON" (ON).
4. Select item #74 from the menu "SERVICE DATA" tester (fuel pressure control).
5. Crank the engine with the starter for 2 seconds or more and visually check that there is no fuel leakage from the connections.
Caution: If there are fuel leaks, immediately stop cranking the engine with the starter and eliminate the source of the leak.
6. Turn the crankshaft of the engine with a starter and after 20 seconds check the fuel pressure.
The minimum allowable value is 1 MPa
Attention: if the fuel pressure is less than 1 MPa, then there are probably leaks in the high pressure line - perform an appropriate check.
7. Turn off the ignition.
8. Connect the intermediate connector of the injectors.
9. Checking the fuel pressure in the high pressure line.
A) Start the engine and leave it to idle.
b) When the engine is idling, measure the fuel pressure in the line.
Nominal pressure - 4-6.9 MPa
V) Check that the fuel pressure at idle does not drop, even after a few presses on the accelerator pedal (to increase the engine speed).
G) If any of the pressure test results are abnormal, then troubleshoot and correct them according to the table "The results of checking the fuel pressure in the high pressure line".
10. Turn off the ignition (turn off the engine).
11. Disconnect the tester.
Checking the tightness of the fuel system (using a tester)
1. Connect a tester to a diagnostic socket.
2. Disconnect the intermediate connector of the injectors.
Engine 4G15.
Engine 4G93.
Table. The results of checking the fuel pressure in the high pressure line
3. Turn on the ignition.
4. Select item #74 from the menu "SERVICE DATA" tester.
5. Crank the engine with the starter for 2 seconds or more and visually check that there is no fuel leakage from the connections.
Caution: If there are fuel leaks, immediately stop cranking the engine with the starter and eliminate the source of the leak.
6. Turn the crankshaft of the engine with a starter and after 20 seconds check the fuel pressure.
The minimum allowable value is 1 MPa
Attention: if the fuel pressure is less than 1 MPa, then there are probably leaks in the high pressure line - perform an appropriate check.
7. Turn off the ignition.
8. Connect the intermediate connector of the injectors.
9. Disconnect the tester.
Removal of residual pressure from the high pressure line (using a tester)
Note: since the fuel line is under pressure, before removing the components of the fuel system (hoses, pipes, etc.) perform this operation to reduce the fuel pressure and prevent it from splashing.
1. Loosen the fuel filler cap to relieve pressure in the tank.
2. Remove the rear seat cushion.
3. Remove cover and service port gasket.
4. Disconnect the fuel pump harness connector.
5. With the ignition off, connect the tester to the diagnostic socket.
6. Turn on the ignition and select item No. 74 from the menu "SERVICE DATA" tester (fuel pressure control).
7. Crank the engine with the starter for 2 seconds or more.
8. If the engine does not start, use a tester to make sure that the pressure is less than 0.5 MPa, then turn off the ignition.
9. If the engine starts, bleed the residual pressure from the fuel lines as follows:
- A) Turn off the ignition (turn off the engine).
- b) Disconnect the electrical connector of one of the ignition coils.
- V) Crank the engine with the starter for 2 seconds or more.
- G) If the engine does not start, use a tester to make sure that the pressure is less than 0.5 MPa and turn off the ignition.
- d) If the engine starts, press the accelerator pedal to increase the engine speed until the engine stalls. Then, using a tester, make sure that the pressure is less than 0.5 MPa and turn off the ignition.
- e) Connect the electrical connector to the ignition coil.
Caution: Clean the spark plug associated with the ignition coil whose connector has been disconnected.
10. Disconnect the tester.
11. Connect the fuel pump harness connector.
12. Install gasket and service port cover.
13. Install the rear seat cushion.
Checking the operation of the low pressure fuel pump
The verification procedure is given in the corresponding section of the chapter "fuel injection system (MPI)".