 printable version
Inspection and detection of defects
Leak test vacuum and air hoses When tightness inlet hose to the engine, usually supplied excess air. This will affect the operation of some electrical components such as control of idling and the oxygen sensor. If the vehicle continues to operate in violation of tightness of hoses, adaptive values will be different from normal and it becomes possible to check the fault codes associated with the adaptive control of the composition of the mixture.
Air filter and an air inlet When clogged air filter or air intake to the engine is insufficient air flow. This is particularly noticeable when accelerating under heavy load.
A WARNING 1) When connecting or disconnecting the measuring unit BU or the ignition must be turned off and the negative battery cable is disconnected. Control units must be removed, for example, drying in an oven after painting. Blocks should not be exposed to temperatures above 80 ?� C. When carrying out welding work using an electric welding disconnect connectors BU. It is necessary to remove the rig when welding work is performed in the immediate vicinity. When replacing the ECU wiring and check the status of system components in order to avoid failure of the new unit because of unresolved faults; 2) It is necessary to turn off the ignition when: - Connect or disconnect the test equipment; - Connect or disconnect connectors BU; - Connect or disconnect the ignition coil and spark plug wires; - The production of measuring resistance using an ohmmeter; 3) When checking compression: - Disconnect the connector of the ignition (to prevent the breakdown in the electrical system wiring harness); - Disconnect the injector connectors (to prevent ingress of fuel into the engine oil); 4) During testing of the various components is important to ensure that the battery voltage is normal (about 12 V). If necessary, during the test, you can plug in the charger. Maximum permissible charging current 15 A. Do not disconnect the wires with the engine running. In rapid charging, disconnect the wires from the battery; 5) When starting the engine from an external source is not allowed to use the device for fast charge or voltage source with a maximum of 16 V. It is necessary to exercise the utmost caution to prevent sparks, especially when testing injectors. Since the ignition system operates at high voltages, touching a high-voltage circuit components such as the ignition coil, spark plug, it is dangerous. Hazardous voltage is present in the whole system, connectors, and so forth. 6) The purity is especially important in the operations of the fuel system; 7) Before removing the connectors thoroughly clean fuel; 8) When you reconnect elements always use new seals. |
Continuous operation of the car with a clogged air filter or air intake can cause distinct adaptive values of normal.
Exhaust When tightness of the exhaust pipe may sucking in air as a result of pressure fluctuations. If the violation occurs above the leakage of the oxygen sensor, the system will interpret this as a lean-burn operation and accordingly there will be changes in the function of the adaptive control of the mixture. Continuous operation of the car with a leaking exhaust system can cause distinct adaptive values of normal and lead to a failure in the system of registration of the adaptive control of the mixture.
Sprayers When clogged nozzle (or nozzles) in the engine will be fed less fuel. This can cause erratic idling.
Fuel pressure The technical specifications the fuel pressure necessary for the injection volumes required. Low pressure fuel is causing the engine operation repauperization mixture and pressure exaggerated compared to the normal causes pereobogaschenie fuel mixture. Continuous operation of the car in the conditions of high or low pressure can cause differences between the adaptive values of normal and lead to the registration of fault codes in the system controlling the composition of the mixture. Residual fuel pressure Low residual pressure is an indication of leakage of the pressure regulator or injector. This could cause malfunctions when starting a warm engine. Continuous operation of the car when tightness in the nozzle may cause differences between the adaptive values of normal and lead to the registration of fault codes in the system controlling the composition of the working mixture.
Fuel filter When clogging of the fuel filter the fuel pressure is lowered, thus causing malfunctions typical cases described above under "fuel pressure" and "residual pressure". Continuous operation of the car in the conditions when the fuel pressure is too low, can cause differences between the adaptive values of normal and lead to the registration of fault codes in the system controlling the composition of the mixture.
Fuel pump Faulty fuel pump may cause lowering the fuel pressure, with the result that there may be failures specific to the cases described in paragraphs "Fuel Pressure" and "residual pressure." Continuous operation of the car in the conditions when the fuel pressure is too low, can cause differences between the adaptive values of normal and lead to the registration of fault codes in the system controlling the composition of the mixture. The system of protection against the emission of fuel vapors (CIPB) Fault in CIPB can lead to uncontrolled absorption of gasoline vapors. Continuous operation of the car with a fault in the system CIPB may cause differences between the adaptive values of normal and lead to the registration of fault codes in the system controlling the composition of the mixture.
Throttle When enough throttle to the motor is not enough air and may stall. If it is opened excessively, gasoline vapors can be absorbed through the CIPB, forming a rich fuel mixture.
Compression Unstable compression can cause a bad pickup, power loss and unstable operation of the engine. Especially it is noticeable when idling. Installation of a camshaft Wrong position of the camshaft relative to the crankshaft can cause early or late opening of the valves and, consequently, the loss of engine power.
Blow Hose crankcase ventilation system is connected to the intake manifold and removes oil mist from the crankcase. If you exceed the level of oil or contamination of its gasoline-fuel mixture will be too rich, so that failure occurs adaptive control function of the mixture. Prolonged operation with a dirty car engine oil may cause differences between the adaptive values of normal and lead to the registration of fault codes in the system controlling the composition of the mixture.
Flywheel Speed sensor and crankshaft position signals a fault in the ECU if the flywheel has undergone deformation or other damage. Leading the drive for engines with automatic transmission is very sensitive to mechanical stress. For this reason it is not recommended to be used for locking or crank the engine. Damage to the drive plate is fraught with the emergence of failures when starting the engine and may cause its unstable operation.
Spark plug Wear spark plug adversely affects the combustion of the fuel. The most common symptoms when worn spark plugs is unstable operation of the engine at idle and increased level of HC (hydrocarbons). Check performance fuel pump
Switch off the ignition.
| Fig. 9.6. Check performance fuel pump
|
Disconnect the drain hose from the pressure regulator and connect instead a hose end lower volumetric capacity. Remove the engine control system relay. Jumper switch contact base 2 and 8 (Fig. 9.6) for 30 s. Normal capacity at a voltage 12 V - 0.83 liters at 12.5 - 1 liter. Check the pressure in the fuel system Switch off the ignition. Remove the cap from the service fitting and attach to it a pressure gauge. Remove the system relay and Jumper pins 2 and 8 (Fig. 9.6). With steady pressure, turn off the fuel pump. The normal pressure of about 300 kPa. Remove the pressure gauge reading after 20 minutes. It must not be less than 200 kPa. If the pressure is less, then the system is leaking.
Checking injectors
| Fig. 9.7. Check the nozzle: a - check the winding resistance injectors; b - check the voltage on the windings of the nozzle
|
The shape of the fuel nozzles of the torch at all to be the same. If the shape of the flame of one of the nozzles is different nozzles need cleaning. Under pressure, closed nozzle should pass no more than one drop per minute. Winding resistance injectors (Fig. 9.7) is equal to: - For the earlier models - about 12 ohms; - For late models - 14-15 ohms. The voltage measured between the 1st pin of the nozzle and the ground "-" (Fig. 9.7) of the car should be about 12 volts while cranking the engine.
Checking the position sensor Throttle
| Fig. 9.8. Check the throttle position sensor: a - resistance test; b - Check voltage
|
With the ignition off, disconnect the sensor connector and measure the resistance between its findings and C (Fig. 9.8). Gently rotate the valve from one extreme to the other. The resistance should vary from 1330 ohms (with open shutter) to 2260 ohms (when closed). Check the power supply connector, which switch on the ignition and measure the voltage between terminals A and B. It should be about 5 V. Checking the air pressure sensor in the intake manifold Switch off the ignition and after disconnecting the sensor on again.
| Fig. 9.9. Check the voltage sensor of the absolute air pressure in the intake manifold
|
Measure the voltage between the terminal wiring connector A and C (Fig. 9.9). It should be about 5 V. To test the sensor with the ignition off gently pull, do not disconnect the connector to provide access to the terminals. Measure the voltage between the connector contact and "weight" in two modes: 1. Ignition on - In 4-4.5 2. Idling - 0.9-1.5 V. If the voltmeter shows these values, the sensor is operational.
Check the temperature sensor air Temperature sensor at 20 ?� C should have a resistance of 3,000-4,000 ohms.
| Fig. 9.10. Measure the resistance and voltage on the sensor temperature
|
The voltage at the sensor connector with the ignition between terminals 1 and 2 (Fig. 9.10) should be about 5 V. The voltage sensor is connected and the ignition is switched between the second terminal connector and "weight" at a temperature of 20 ?� C should be about 2 V.
Check the Control knob idling
| Fig. 9.11. Measure the resistance and voltage regulator on idling
|
With the ignition off, disconnect the connector valve and measure the resistance between the contacts (Fig. 9.11). It should be 8-11 ohms. Check the voltage between pin 1 and "weight". It should be about 12 V. Check the ignition coil
| Fig. 9.12. Measure the resistance and voltage when checking the ignition coil
|
To check the voltage with the ignition off, disconnect the electrical connector of the coil, set the voltmeter between terminal 3 (Fig. 9.12) wiring connector and "weight" and scroll through the starter motor. The voltmeter should show the battery voltage. To check the primary winding of the resistance between terminals 1 and 3 of the ignition coil. It should be 0.5-1 ohm. Secondary resistance should be 10 200 Ohm.
Checking the position sensor Crankshaft
| Fig. 9.13. Measure the resistance and voltage checking the crankshaft position sensor
|
With the ignition off, disconnect the connector and measure the resistance of the sensor (Fig. 9.13). It should be 200-350 ohms. With the ignition off, disconnect the injector connectors and disconnecting the sensor connector, connect a voltmeter to the pin terminals. (scale AC). Crank the engine starter. Between contacts should be the ripple voltage of 1.8 V. To test the control voltage is disconnected to the wiring connector with the ignition on, measure the voltage between terminals 1 and "mass" and 2 "mass". In both cases, the voltage to be 3.3 V.
Check Oxygen Sensor To check with the ignition off, disconnect the sensor electrical connector. Turn on the ignition. Measure the voltage between terminals 1 and "weight" and the contact 4 and the "weight". Between 4 contact and "weight" should be the voltage of 0.4 V.
| 
