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Troubleshooting - general information and preliminary checks

Refer also to Section Diagnostics of malfunctions and Materials Parts Diagnostics of systems of electronic control and diagnostic equipment.

The ignition system and fuel system are interrelated components of the engine management system, so some of its components may also perform certain functions related to the operation of the fuel system.

general information

The ignition system and the fuel system have a common diagnostic system designed to save the trouble code (DTC) and diagnosis. In identifying the failure of the control unit stores the processor corresponding code DTC, representing a sequence of signals that can be read with a special scanner (see. Part Diagnostics of systems of electronic control and diagnostic equipment).

Reading of information stored in the processor memory ECM in most cases to determine the causes of failures in the motor vehicle. Analysis of the read information with the code list (see. Specifications) allows you to locate the source of failure at the level of a particular element, or its electrical circuit.

Visual inspection of wiring and connectors is not enough - must consider the information stored in the memory of the control module!

Preliminary checks

If the problem occurred shortly after the service of a node, we must first scrutinize the node and located adjacent components - it is possible that the cause of the failure is related to the violation of the basic quality of contact connection.

During the search for the causes of infringement of serviceability of functioning of the engine (for example, the drop developed capacity) always makes sense to check the cylinder compressions. Make sure that the replacement of the air and fuel filters made in accordance with the maintenance schedule (see chap. Current care and maintenance).

Remember that after reading fault codes and make the appropriate corrections memory management module should be cleaned (see. Part Diagnostics of systems of electronic control and diagnostic equipment).

PERFORMANCE ORDER

Open the hood and check the reliability of fixing of tips of wires on the pole terminals of the battery, make sure that there are no signs of oxidation of terminal connections. If necessary, make appropriate measures to deal with problems (see chap. Current leaving and service), defective components replace. No less carefully examine the tires and the ground terminal connections - contact surface of the respective elements of supply (power unit / body panels) must be completely clean and free of corrosion. Next, inspect all visible wiring sandwiched within the engine compartment, check the contact connections. With pronounced signs of damage, replace the wiring harness, making sure wiring harness, if necessary tighten fasteners unnerved nodes on which frayed insulation. Risk area are always areas wiring passing near serviceable parts are produced in the most recent time. It should be remembered that the grounded conductor wiring can be damaged with no signs of damage to the insulation - in this situation, the external examination will not give positive results. Such injuries can result from pulling the wires, or in violation of the route of the cables. Restore the wiring can be damaged by soldering on the site break bridging veins - ration provides a reliable electrical contact. To repair the insulation, use insulating tape or set him on the wire cut heat shrink tubing. Remember that the best (if not the cheapest) way to eliminate all associated with damage to the electrical failure is the replacement of faulty wires. After finishing the refurbishment / replacement of picking, track correctness pads associated wiring, paying particular attention to portions of routes warmed up near the surface and moving parts in the engine compartment. Track reliability of fixing harnesses all provided intermediate clamps. Check all terminal connections are available, check the mounting pin connector wiring. If any connector on the inner surface corrosion (white or green deposits / rust), and the excessive contamination, remove the connector with appropriate terminals and clean them, if necessary, by using a special spray. Seriously damaged connectors to be replaced - in some cases, complete with cable harness. After cleaning the connectors from corrosion tamp it before reinstalling the preservative grease - if necessary, consult with experts of car-care center. In all covered in this manual models use an inductive crankshaft position sensor (CKP), by which is also determined by TDC of first cylinder. Excessive dirt / dusty sensor can cause misfiring. The description of procedures of removal / installation of the CKP sensor is presented below in the corresponding section of this part of the Head of System of an electric motor. Inspect hoses and tubes of all vacuum lines the engine compartment. Check tightening of fixing clamps, make sure there is no deformation, cracks, cuts, bundles, and other physical damage hoses / tubes. Carefully read choke assemblies for signs of leakage. Particular attention should be paid to the state lines laid near sharp edges. Loss of vacuum is usually accompanied by a characteristic whistling in identifying a suspect portion of the hose must be lubricated with soapy water - the source of the leak can be considered to be detected if the substrate solution stability of the engine speed increases. Pull the slack clamps, replace the damaged line. Assess the permeability of the hose and check the crankcase ventilation system - the number of hoses and place of installation depends on the model of the car, however, on all engines used, connecting the upper portion of the power unit sleeve inlet air path or the intake manifold. Some hoses are used for connection to the intake manifold cylinder / oil filler cap, - on them crankcase gases are discharged into the combustion chambers of the cylinders. Excessive pollution or violation of cross ventilation hoses entails infringement of stability of turns - especially blanks - engine. Moving from the fuel tank to the fuel distribution line (via fuel) filter along the fuel lines, carefully examine the condition of the fuel lines. Pay special attention to places of articulation tubes, where most cracks through which begin to develop leaks. Damaged sections replace fuel lines. Remove the air cleaner cover and check the condition of the filter element. Excessively dirty filter can significantly increase the total aerodynamic resistance of the air intake tract, which directly affects the power developed by the engine. If necessary, replace the filter element. Start the engine and leave it running at idle. When performing any work in the engine compartment with the engine running, observe extreme caution - be careful not to touch the heated surfaces of the power unit and exhaust system, do not expose the hair strands and free items of clothing in the moving parts (cooling fan, belt drive accessory)! Moving from the air intake to the air cleaner and beyond - to the throttle body, make sure that there are no signs of development of leaks of air in the intake tract. To identify sources of leaks can be re-use soap. Make the necessary corrections. Drive the vehicle on a lift and examine the state of the components of the exhaust system. Make sure there are no signs of leaks, - the easiest way to detect leakage of the exhaust tract is possible by plugging its outlet - the characteristic whistles and smoke to help locate the damaged area. Pull weakened collars / replace defective seals, set to replace damaged a new section (s). The final stage of testing, start the engine and turn tug his electrical connectors - the poor quality of contact will indicate the changing nature of the engine - make the necessary corrections / replace defective wiring areas. If in the course of preliminary checks to identify the cause of instability of the engine fails, the car should be driven away on a service to perform a more thorough diagnosis using special equipment.