A fundamental step in identifying the cause of any failure is to select a starting point for the search. Often the cause is fairly obvious, but in some cases it takes some work to do a little research. A car enthusiast who has made half a dozen random checks, replacements and corrections has a good chance of discovering the cause of the failure (or its symptom), However, this approach cannot be considered reasonable in any way, due to its laboriousness and aimlessness of time and money. A calm, logical approach to finding a failed node or component is much more effective. Be sure to take into account all the preceding failure, sometimes minor symptoms and warning signals, such as loss of power developed by the engine, changes in meter readings, the occurrence of unusual sounds and smells, etc. Keep in mind that failure of components such as fuses or spark plugs may only be a symptom of a deeper problem.
Below in this subsection, a fairly simple scheme for diagnosing the most frequently occurring failures is given. The causes of violations and their symptoms are grouped according to their relationship to the functioning of a particular unit or system, for example: Engine, Cooling system, etc. In parentheses are links to the relevant Chapters and Sections of the Manual that are relevant to the functioning of the components suspected of malfunctioning.
Regardless of the nature of the failure, the investigation of its cause is always based on the same basic principles:
- Make sure you identify the symptoms of rejection correctly. This means confidence in determining the boundaries of the search area, which is especially important in helping to diagnose a failure to another motorist who cannot adequately state the symptoms of an existing violation.
- Try not to overlook obvious violations. For example, if the engine won't start, feel free to check for fuel in the gas tank (at the same time, the statements of the owner of the faulty car should not be taken for granted). In the event of a failure of electrical equipment, first of all, you should check the condition and reliability of fastening of the terminal connections of the electrical wiring, only after that it makes sense to get diagnostic tools.
- Try to address the cause of the failure, not its symptom. Replacing a dead battery with a new one will help start the engine, but the underlying cause of the old battery's discharge will remain uncorrected, leading to a quick failure of the new one. Also replacing oiled spark plugs (petrol models) will allow you to restore the correct functioning of the engine for a while, but its failure will certainly repeat soon (if the reason lay not simply in the use of candles of the wrong type).
- Don't take any statements for granted. remember, that "new" a component can also be defective, especially if it has been in the trunk for a long time - you should not exclude a component from the list of checks just because it is new or recently installed. In case of neglecting the implementation of this recommendation, one should not be surprised when the reason for the failure finally revealed turns out to be lying on the surface from the very beginning.
Diagnosis of common engine failures
Engine won't crank when trying to start it
The battery terminals are oxidized, or the wire lugs are loose on them (see chapter Current service).
Low or defective battery (see chapter Engine electrical equipment).
The electrical wiring of the starting system circuit is broken or otherwise damaged, or the fastening of the terminals of the contact connections is loose (see chapter Engine electrical equipment).
Faulty starter relay or ignition switch (see chapter Engine electrical equipment).
Faulty starter motor (see chapter Engine electrical equipment).
Broken or worn starter drive gear teeth or flywheel crown (see chapter Engine electrical equipment).
The motor ground bus is broken, or its terminal connection is loose (see chapter Engine electrical equipment).
Engine cranks but won't start
Empty fuel tank.
Low battery (engine cranks too slowly) (see chapter Engine electrical equipment).
The battery terminals are oxidized, or the wire lugs are loose on them (see chapter Current service).
Moistened or damaged ignition system components - petrol models (see chapter Engine electrical equipment).
The setting of the ignition timing is violated (see chapter Engine electrical equipment).
Ignition circuit wiring broken or otherwise damaged, or terminals of contact connections loosened - gasoline models (see chapter Engine electrical equipment).
Worn or damaged spark plugs, or incorrect electrode gap setting - petrol models (see chapter Current service).
Faulty preheating system - diesel models (see chapter Engine electrical equipment).
Faulty fuel supply system - petrol models (see chapter Power systems).
Faulty Solenoid Fuel Shutoff Valve - Diesel Models (see chapter Power systems).
Air got into the power system - diesel models (see chapter Power systems).
There is mechanical damage to the engine (e.g. camshaft drive).
Difficulty starting a cold engine
Low battery (see chapter Engine electrical equipment).
The setting of the ignition timing is violated (see chapter Engine electrical equipment).
The battery terminals are oxidized, or the wire lugs are loose on them (see chapter Current service).
Worn or damaged spark plugs, or incorrect electrode gap setting - petrol models (see chapter Current service).
Faulty preheating system - diesel models (see chapter Engine electrical equipment).
Faulty fuel injection system - petrol models (see chapter Power systems).
Dirty carburetor (see chapter Power systems).
The lever for smooth adjustment of automatic start is stuck - carburetor models (see Power systems).
Idle speed adjustment is broken, or throttle valves are incorrectly installed - carburetor models (see chapter Power systems).
The functioning of the forced idle shut-off solenoid valve is disrupted - carburetor models (see chapter Power systems).
The tightness of the carburetor assembly is broken (see chapter Power systems).
Corroded throttle cable.
Faulty ignition system - petrol models (see chapter Engine electrical equipment).
Compression pressure dropped (see chapter Engine).
Difficulty starting a hot engine
Wrong type of fuel filled.
The air cleaner filter element is dirty, or its patency is otherwise impaired (see chapter Current service).
Faulty fuel injection system - petrol models (see chapter Power systems.
Interrupted fuel supply to the carburetor (see chapter Power systems).
Carburetor spilled (see chapter Power systems).
Dirty idle system - carburetor models (see chapter Power systems).
The functioning of the forced idle shut-off solenoid valve is disrupted - carburetor models (see chapter Power systems).
The tightness of the needle valve is broken - carburetor models (see chapter Power systems).
The tightness of the float is broken - carburetor models (see chapter Power systems).
The tightness of the carburetor assembly is broken (see chapter Power systems).
Compression pressure dropped (see chapter Engine).
The setting of the ignition timing is violated (see chapter Engine electrical equipment).
Entering the starter into gear is difficult, or accompanied by extraneous noise
Broken or worn starter drive gear teeth or flywheel crown (see chapter Engine and Chapter Engine electrical equipment).
Loose or loose starter mounting bolts (see chapter Engine electrical equipment).
Worn or damaged internal starter components (see chapter Engine electrical equipment).
Engine starts but immediately stalls
Ignition circuit wiring broken or otherwise damaged, or terminals of contact connections loosened - gasoline models (see chapter Engine electrical equipment).
There is vacuum loss at the throttle body or intake piping - petrol models (see chapter Power systems).
The patency of the injector is broken / the power supply system is faulty - gasoline models (see chapter Power systems).
Idle speed stability is broken
Air cleaner element blocked (see chapter Current service).
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
Worn or damaged spark plugs, or incorrect electrode gap setting - petrol models (see chapter Current service).
Compression pressure dropped or unevenly distributed between the cylinders (see chapter Engine).
Camshaft lobes worn out (see chapter Engine).
Timing belt/chain tension incorrectly adjusted (see chapter Engine).
The patency of the injector is broken (ov) /faulty power system - petrol models (see chapter Power systems).
Faulty injector (And) fuel injection - diesel models (see chapter Power systems).
Ignition misfire occurs at idle
Worn or damaged spark plugs, or incorrect electrode gap setting - petrol models (see chapter Current service).
Faulty BB spark plug wires - petrol models (see chapter Engine electrical equipment).
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
The patency of the injector is broken (ov) /faulty power system - petrol models (see chapter Power systems).
Faulty injector (And) fuel injection - diesel models (see chapter Power systems).
The distributor cap is cracked, or carbon paths have formed inside it - gasoline models with the appropriate equipment (see chapter Engine electrical equipment).
Compression pressure dropped or unevenly distributed between the cylinders (see chapter Engine).
Damaged, worn or disconnected crankcase ventilation hoses (see chapter Power systems).
Misfire occurs while driving in gear
The patency of the fuel filter is broken (see chapter Current service).
The fuel pump is faulty, or the pressure it develops has fallen - gasoline models (see chapter Power systems).
The ventilation of the fuel tank is broken, or the fuel lines are blocked (see chapter Power systems).
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
Worn or damaged spark plugs, or incorrect electrode gap setting - petrol models (see chapter Current service).
Faulty BB spark plug wires - petrol models (see chapter Engine electrical equipment).
Faulty injector (And) fuel injection - diesel models (see chapter Power systems).
The distributor cap is cracked, or carbon paths have formed inside it - gasoline models with the appropriate equipment (see chapter Engine electrical equipment).
Faulty ignition coil - petrol models (see chapter Engine electrical equipment).
Compression pressure dropped or unevenly distributed between the cylinders (see chapter Engine).
The patency of the injector is broken (ov) /faulty power system - petrol models (see chapter Power systems).
The stability of the engine speed is violated during acceleration
Worn or damaged spark plugs, or incorrect electrode gap setting - petrol models (see chapter Current service).
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
Dirty carburetor (see chapter Power systems).
Incorrectly installed jets - carburetor models (see chapter Power systems).
Idle speed adjustment is broken - carburetor models (see chapter Power systems).
Serviceability of functioning of the accelerating pump of the carburetor is broken (see chapter Power systems).
The tightness of the carburetor assembly is broken (see chapter Power systems).
Incorrectly adjusted throttle position of chamber II of the carburetor (see chapter Power systems).
The tightness of the vacuum booster of chamber II is broken, or the cable of the wrong length is installed - carburetor models (see chapter Power systems).
The patency of the injector is broken (ov) /faulty power system - petrol models (see chapter Power systems).
Faulty injector (And) fuel injection - diesel models (see chapter Power systems).
The engine spontaneously stalls
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
The patency of the fuel filter is broken (see chapter Current service).
The fuel pump is faulty, or the pressure it develops has fallen - gasoline models (see chapter Power systems).
The ventilation of the fuel tank is broken, or the fuel lines are blocked (see chapter Power systems).
The patency of the injector is broken (ov) /faulty power system - petrol models (see chapter Power systems).
Faulty injector (And) fuel injection - diesel models (see chapter Power systems).
Decreased engine power
Violated valve clearance adjustment - 1.3 l models (see chapter Current service).
The timing belt / chain is not installed correctly, or the adjustment of its tension force is violated (see chapter Engine).
The patency of the fuel filter is broken (see chapter Current service).
The fuel pump is faulty, or the pressure it develops has fallen - gasoline models (see chapter Power systems).
Iced carburetor (see chapter Power systems).
Incorrectly installed jets - carburetor models (see chapter Power systems).
The serviceability of the air-fuel mixture enrichment system at full engine load is broken - carburetor models (see chapter Power systems).
The tightness of the carburetor float is broken (see chapter Power systems).
The adjustment of the throttle valve of chamber II of the carburetor is broken (see chapter Power systems).
The tightness of the vacuum booster of chamber II is broken, or the drive cable is installed the wrong length - carburetor models (see chapter Power systems).
The setting of the ignition timing is violated (see chapter Engine electrical equipment).
Compression pressure dropped or unevenly distributed between the cylinders (see chapter Engine).
Worn or damaged spark plugs, or incorrect electrode gap setting - petrol models (see chapter Current service).
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
The patency of the injector is broken (ov) /faulty power system - petrol models (see chapter Power systems).
Faulty injector (And) fuel injection - diesel models (see chapter Power systems).
The installation of the injection phases of the high-pressure fuel pump is violated - diesel models (see chapter Power systems).
Sticky brakes (see chapters Current service and Brake system).
Clutch slips (see chapter Clutch).
Happening "shots" in the exhaust system
The timing belt / chain is not installed correctly, or the adjustment of its tension force is violated (see chapter Engine).
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
The patency of the injector is broken (ov) / faulty fuel injection system - petrol models (see chapter Power systems).
Idle speed adjustment is broken, or throttle valves are incorrectly installed - carburetor models (see chapter Power systems).
The adjustment of the accelerator pump of the carburetor is broken (see chapter Power systems).
The tightness of the carburetor assembly is broken (see chapter Power systems).
The setting of the ignition timing is violated (see chapter Engine electrical equipment).
The oil pressure warning light stays on while the engine is running
The oil level has dropped, or the wrong type of oil has been filled (see chapter Current service).
Faulty oil pressure switch (see chapter Engine electrical equipment).
Worn engine bearings and/or oil pump (see chapter Engine).
Engine operating temperature is too high (see chapter Cooling, heating systems).
Faulty oil pressure reducing valve (see chapter Engine).
Violated patency of the mesh filter of the oil intake (see chapter Engine).
The engine continues to run after the ignition is turned off
There is excessive carbon build-up in the engine (see chapter Engine).
Engine operating temperature is too high (see chapter Cooling, heating systems).
Faulty power system - petrol models (see chapter Power systems).
Faulty fuel cut-off shut-off valve - diesel engines (see chapter Power systems).
Extraneous noises during engine operation
Knocks caused by too early ignition or detonation during acceleration or when the load is increased
Ignition advance setting is violated / ignition system is faulty - gasoline models (see chapter Engine electrical equipment).
Wrong type of spark plugs installed - gasoline engines (see chapter Current service).
Wrong type of fuel filled (see chapter Power systems).
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
There is excessive carbon build-up in the engine (see chapter Engine).
The patency of the injector is broken (ov) /faulty power system - petrol models (see chapter Power systems).
Whistling or hissing
Vacuum loss occurs at the throttle body, intake piping or connecting hoses - petrol models (see chapter Power systems).
There are exhaust gas leaks in the exhaust system or through the junction of the exhaust pipe with the exhaust manifold (see chapter Power systems).
There are vacuum losses through the vacuum hoses.
Broken cylinder head gasket (see chapter Engine).
Screech or rumble
Violated valve clearance adjustment - 1.3 l models (see chapter Current service).
Worn valve drive components or camshaft (see chapter Engine).
Worn hydraulic valve lifters (see chapter Engine).
Auxiliaries faulty (water pump, generator, etc.) (see chapter Cooling, heating systems, chapter Engine electrical equipment, etc.).
Thud
Worn connecting rod bearings (regular heavy knocking, sometimes decreasing with increasing load) (see chapter Engine).
Worn crankshaft main bearings (rumbling, possibly increasing with increasing load) (see chapter Engine).
The knock of pistons (most intense with a cold engine) (see chapter Engine).
Auxiliaries faulty (water pump, generator, etc.) (see chapter Cooling, heating systems, chapter Engine electrical equipment, etc.).
Diagnosis of malfunctions of the cooling system
Overheat
Dropped coolant level in the system (see chapter Current service).
The auxiliary drive belt is broken, or the adjustment of its tension force is broken (see chapter Current service or Engine).
Faulty thermostat (see chapter Cooling, heating systems).
The patency of the radiator is broken or its grille is blocked (see chapter Cooling, heating systems).
The electric fan of the cooling system is faulty, or the temperature-sensitive sensor-switch of its control (see chapter Cooling, heating systems).
Radiator cap damaged (see chapter Cooling, heating systems).
Violated ignition timing adjustment / faulty ignition system - gasoline models (see chapter Engine electrical equipment).
Inaccurate temperature sensor readings (see chapter Cooling, heating systems).
The cooling system path is blocked by an air lock (see chapter Current service).
Hypothermia
Faulty thermostat (see chapter Cooling, heating systems).
Inaccurate temperature sensor readings (see chapter Cooling, heating systems).
There are external coolant leaks
Hoses or hose clamps of the cooling path are damaged mechanically or as a result of aging of the material (see chapter Current service).
Damaged radiator or heater heat exchanger (see chapter Cooling, heating systems).
Faulty radiator cap (see chapter Cooling, heating systems).
Damaged water pump seal (see chapter Cooling, heating systems).
The coolant has boiled due to overheating (see chapter Cooling, heating systems).
Damaged squeeze plugs of the water jacket of the engine block (see chapter Engine).
There are internal coolant leaks
Broken cylinder head gasket (see chapter Engine).
Cracked cylinder head or block (see chapter Engine).
Components are severely corroded
The system is not emptied and flushed often enough (see chapter Current service).
Water and antifreeze mixed incorrectly, or wrong grade of antifreeze used (see chapter Current service).
Diagnostics of malfunctions of systems of food and release of the fulfilled gas
Excessive fuel consumption
The air cleaner element is dirty or otherwise obstructed (see chapter Current service).
Faulty injection system - petrol models (see chapter Power systems).
Dirty carburetor (see chapter Power systems).
Incorrectly installed jets - carburetor models (see chapter Power systems).
Start choke incorrectly set - carbureted models (see chapter Power systems).
Corroded throttle cable (see chapter Power systems).
Automatic carburetor start does not turn off (see chapter Power systems).
The fast idle speed adjustment is violated, or the position of the throttle valves is violated - carburetor models (see chapter Power systems).
Dirty idle system - carburetor models (see chapter Power systems).
The serviceability of the functioning of the air-fuel mixture enrichment system is broken - carburetor models (see chapter Power systems).
The tightness of the needle valve of the carburetor is broken (see chapter Power systems).
The tightness of the carburetor float is broken (see chapter Power systems).
Faulty injector (And) - diesel models (see chapter Power systems).
Ignition advance setting is violated / ignition system is faulty - gasoline models (see chapter Engine electrical equipment).
Insufficient tire inflation pressure (see chapter Current service).
"tacked on" brakes (see chapters Current service and Brake system).
There are fuel leaks or a distinct smell of gasoline
Damaged mechanically or as a result of corrosion of the fuel tank, fuel lines or fittings (see chapter Power systems).
The tightness of the carburetor assembly is broken (see chapter Power systems).
Carburetor flooded during unsuccessful attempts to start the engine (see chapter Power systems).
Excessively noisy or smoking exhaust system
There are exhaust gas leaks through the joints of the exhaust manifold or sections of the exhaust system (see chapter Current service and Chapter Power systems).
Mufflers or pipes of the exhaust system are damaged mechanically or as a result of corrosion (see chapter Current service and Chapter Power systems).
As a result of damage to the suspension mounts, the exhaust system contacts body or suspension components while driving (see chapter Current service).
Clutch Troubleshooting
Clutch pedal sinks to the floor with little or no resistance
Broken clutch cable (see chapter Clutch).
Drive cable misadjusted (see chapter Clutch).
Broken release bearing or clutch release lever (see chapter Clutch).
Broken clutch pressure plate diaphragm spring (see chapter Clutch).
Clutch does not disengage (unable to select gear)
Drive cable misadjusted (see chapter Clutch).
The driven disk is jammed on the splines of the input shaft of the gearbox (see chapter Clutch).
driven disk "stuck" to the surface of the flywheel or pressure plate (see chapter Clutch).
Worn or incorrectly assembled clutch release mechanism (see chapter Clutch).
Clutch slips (engine speed increases without increasing vehicle speed)
Drive cable misadjusted (see chapter Clutch).
Excessively worn friction linings of the driven disc (see chapter Clutch).
The friction linings of the driven disc are contaminated with oil or grease (see chapter Clutch).
Faulty clutch basket or weakened force developed by the diaphragm spring (see chapter Clutch).
Vibration occurs when the clutch is engaged
Excessively worn friction linings of the driven disc (see chapter Clutch).
The friction linings of the driven disc are contaminated with oil or grease (see chapter Clutch).
Jammed or frayed drive cable (see chapter Clutch).
Faulty or deformed pressure plate or diaphragm spring (see chapter Clutch).
Powertrain mounts worn or loose (see chapter Engine).
Worn gearbox input shaft splines or driven disc hubs (see chapter Clutch).
When depressing or releasing the clutch pedal, there are extraneous noises
Worn release bearing (see chapter Clutch).
Worn or dry clutch pedal axle bushings (see chapter Clutch).
Faulty clutch basket assembly (see chapter Clutch).
Pressure plate diaphragm spring broken (see chapter Clutch).
Driven disc torsion springs broken (see chapter Clutch).
Diagnostics of malfunctions of a manual transmission
Gearbox in neutral makes noise when engine is running
Worn input shaft bearings (noises appear when the clutch pedal is released and disappear when it is depressed) (see chapter Transmission) *.
Worn clutch release bearing (noises appear when the clutch pedal is depressed and may decrease when it is released) (see chapter Clutch).
Noises occur in any particular gear
Worn, chipped or otherwise damaged gear teeth (see chapter Transmission) *.
Difficulty shifting gears
Faulty clutch (see chapter Clutch).
Worn or damaged shift drive components (see chapter Transmission).
Worn synchronizer blocks (see chapter Transmission) *.
Box "jumps off" from selected gear
Worn or damaged shift drive components (see chapter Transmission).
Worn synchronizer blocks (see chapter Transmission) *.
Worn shift forks (see chapter Transmission) *.
There are vibrations
Transmission oil level dropped (see chapter Current service).
Worn bearings (see chapter Transmission) *.
Transmission oil leaks
Damaged output differential seal (see chapter Transmission).
Leaks occur through crankcase joints (see chapter Transmission) *.
Damaged input shaft seal (see chapter Transmission) *.
* Although troubleshooting such problems is beyond the skill of the average amateur mechanic, this information will be useful when dealing with a professional.
Diagnosis of malfunctions of drive shafts
There is a rattle and knock during a U-turn (at low speed and the steering wheel turned all the way)
There was a loss of CV joint lubrication, most likely due to damage to the protective cover (see chapter Drive shafts).
Worn outer CV joint of the drive shaft (see chapter Drive shafts).
Vibrations occur during acceleration/deceleration
Worn CV joint (see chapter Drive shafts).
Bent or otherwise deformed drive shaft (see chapter Drive shafts).
Diagnostics of malfunctions of the brake system
Note. Before concluding that the brake system has failed, check the condition and inflation pressure of the tires and ensure that the vehicle is evenly loaded. Diagnosis of any ABS failures, with the exception of checking the condition of the fitting connections of hydraulic pipes and hoses, should be carried out at a Skoda authorized service station.
When braking, the directional stability of the car is violated
Worn, damaged or oily brake pads / shoes from one of the sides of the car (see chapters Current service and Brake system).
The piston of the caliper / wheel cylinder of one of the mechanisms is jammed, or its movement is difficult (see chapters Current service and Brake system).
Brake pads / shoes with friction linings of various types are installed on different sides of the car (see chapters Current service and Brake system).
Loose caliper or brake shield mounting bolts (see chapter Brake system).
Worn or damaged steering or suspension components (see chapters Current service and Suspension and steering).
Extraneous noises occur during braking (grinding or high-frequency squealing)
Friction linings of brake pads/boots are worn down to metal substrates (see chapters Current service and Brake system).
Corroded brake disc/drum - most likely after a long period of parking (see chapters Current service and Brake system).
A foreign object has fallen between the disc and the shield of the brake mechanism (e.g. stone) (see chapters Current service and Brake system).
Excessive brake pedal travel
The functioning of the automatic adjustment mechanism of the rear brake mechanisms is disrupted - drum mechanisms (see chapters Current service and Brake system).
Faulty GTZ (see chapter Brake system).
Air has entered the hydraulic system (see chapters Current service and Brake system).
Faulty vacuum brake booster (see chapter Brake system).
Faulty vacuum pump - diesel models (see chapter Brake system).
There is a softness of the brake pedal when it is squeezed out
Air has entered the hydraulic system (see chapters Current service and Brake system).
Flexible brake hoses damaged due to material aging (see chapters Current service and Brake system).
Loose nuts securing the GTS (see chapter Brake system).
Faulty GTZ (see chapter Brake system).
Applying too much force to the brake pedal is required to stop the vehicle
Faulty brake booster unit (see chapter Brake system).
Faulty vacuum pump - diesel models (see chapter Brake system).
Damaged or disconnected brake booster vacuum hoses or loose fittings (see chapter Brake system).
Faulty primary or secondary hydraulic circuit (see chapter Brake system).
Piston stuck (And) caliper/wheel cylinder (see chapter Brake system).
Brake shoes/pads installed incorrectly (see chapters Current service and Brake system).
Wrong type of chocks/shoes fitted (see chapters Current service and Brake system).
Friction linings of brake pads/shoes are dirty (see chapters Current service and Brake system).
During braking, vibration is transmitted to the brake pedal or steering wheel
Excessive brake disc runout/brake drum deformation (see chapters Current service and Brake system).
Worn friction linings of brake pads/boots (see chapters Current service and Brake system).
Loose caliper/brake plate mounting bolts (see chapter Brake system).
Worn suspension or steering components or bearings (see chapters Current service and Suspension and steering).
There is a pulsation of the foot brake pedal when it is squeezed out during hard braking
A consequence of the correct functioning of the ABS (see chapter Brake system).
Brakes "seized"
(see chapters Current service and Brake system).
Piston stuck (And) brake caliper/wheel cylinder (see chapter Brake system).
Parking brake adjustment out of order (see chapter Brake system).
Faulty GTZ (see chapter Brake system).
Rear wheels lock up under normal braking
The friction linings of the brake shoes are dirty.
There is a deformation of the discs / drums of the rear brake mechanisms (see chapters Current service and Brake system).
Suspension and steering fault diagnosis
Note. Before testing suspension and steering components, make sure the problem is not caused by incorrect tire inflation, different tire sizes, or "tacking" brakes.
Violated directional stability of the car
There is a defect in the tires (see chapter Current service).
Tires are inflated at different pressures (see above in Introduction).
Worn suspension or steering components (see chapters Current service and Suspension and steering).
Adjustment of angles of installation of forward wheels is broken (see chapter Suspension and steering).
Suspension or steering components damaged in an accident (see chapter Current service).
There is wheel play and increased vehicle vibration
Front wheel imbalance (vibration is transmitted most noticeably through the steering wheel) (see chapter Current service).
Rear wheel imbalance (vibration is transmitted most noticeably through the body of the car) (see chapter Current service).
Damaged or warped wheels (see chapters Current service and Suspension and steering).
Tires damaged (see chapter Current service).
Worn steering or suspension components, or their ball joints and/or rubber-metal bushings (see chapters Current service and Suspension and steering).
Loose wheel bolts (A) (see chapter Current service).
During cornering and braking, "galloping" and/or vehicle rocking
Defective shock absorbers (see chapters Current service and Suspension and steering).
Worn steering or suspension components, or their ball joints and/or rubber-metal bushings (see chapters Current service and Suspension and steering).
Worn or damaged stabilizer bar or its support (see chapter Suspension and steering).
There is yaw or general vehicle yaw
Adjustment of angles of installation of forward wheels is broken (see chapter Suspension and steering).
Worn steering or suspension components, or their ball joints and/or rubber-metal bushings (see chapters Current service and Suspension and steering).
Wheel balance out of alignment (see chapters Current service and Suspension and steering).
Tires faulty (see chapter Current service).
Loose wheel bolts (A) (see chapter Current service).
Defective shock absorbers (see chapters Current service and Suspension and steering).
Steering wheel too hard to turn
Low power steering fluid level (see chapter Current service).
Lack of steering gear lubrication (see chapter Suspension and steering).
Stuck tie rod end or ball joint (see chapters Current service and Suspension and steering).
The auxiliary drive belt is broken, or the adjustment of its tension force is broken (see chapter Current service).
Adjustment of angles of installation of forward wheels is broken (see chapter Suspension and steering).
Bent or damaged steering rack or column (see chapter Suspension and steering).
Violated patency of the tract of the hydraulic power steering system (see chapter Suspension and steering).
Steering pump defective (see chapter Suspension and steering).
Excessive steering wheel play
Worn universal joint (s) steering column intermediate shaft (see chapter Suspension and steering).
Worn tie rod ends (see chapters Current service and Suspension and steering).
Worn rack and pinion (see chapter Suspension and steering).
Worn steering or suspension components, or their ball joints and/or rubber-metal bushings (see chapters Current service and Suspension and steering).
No hydraulic boost
The auxiliary drive belt is broken, or the adjustment of its tension force is broken (see chapter Current service or Engine).
Dropped hydraulic fluid level (see chapter Current service).
Violated patency of the hoses of the power steering system (see chapter Suspension and steering).
Steering pump defective (see chapter Suspension and steering).
Defective rack and pinion (see chapter Suspension and steering).
Excessive tire wear
Increased wear on the inside or outside of the tread
Tires under-inflated (wear on both ends) (see chapter Current service).
Violated the adjustment of the camber or longitudinal inclination of the axis of rotation of the wheel (tread wear from one of the edges) (see chapter Suspension and steering).
Worn steering or suspension components, or their ball joints and/or rubber-metal bushings (see chapters Current service and Suspension and steering).
Won't slow down when cornering
There is mechanical damage as a result of the accident.
Scale wear (fraying) protector
Convergence setting violated (see chapter Suspension and steering).
Wear of the central part of the tread
Tires are inflated too much (see chapter Current service).
Wear on the inner and outer edges of the tread
Tires under-inflated (see chapter Current service).
Worn shock absorbers (see chapter Suspension and steering).
Uneven tread wear
Tire/wheel out of balance (see chapter Current service).
Excessive wheel or tire lateral runout (see chapter Current service).
Worn shock absorbers (see chapters Current service and Suspension and steering).
Tire damaged (see chapter Current service).
Diagnostics of malfunctions of electrical equipment systems
Note. Problems associated with a failure in the starting system are discussed above in the Diagnosis of General Engine Failures subsection.
Battery not "keeps" charge
There is an internal battery defect (see chapter Engine electrical equipment).
Decreased electrolyte level in banks (see chapter Current service).
The battery terminals are oxidized, or the wire lugs are loose on them (see chapter Current service).
The drive belt of auxiliary units is worn out, or the adjustment of its tension force is broken (see chapter Current service or Engine).
The generator does not produce the required charge current (see chapter Engine electrical equipment).
Faulty generator voltage regulator (see chapter Engine electrical equipment).
The battery is discharging due to a short circuit in the circuit (see chapter Engine electrical equipment and Chapter Onboard electrical equipment).
Ignition/charge warning lamp stays on while engine is running
Auxiliary drive belt worn or broken or out of adjustment (see chapter Current service).
Worn, jammed or dirty alternator brushes (see chapter Engine electrical equipment).
Weak or broken alternator brush springs (see chapter Engine electrical equipment).
There is an internal defect in the generator or voltage regulator (see chapter Engine electrical equipment).
The charge circuit wiring is broken, or the terminal connections are loose (see chapter Engine electrical equipment).
Ignition/Charge Warning Lamp Does Not Illuminate When Engine Is Started
Burnt out filament (see chapter Onboard electrical equipment).
Broken wiring or loose terminal connections (see chapter Onboard electrical equipment).
Faulty generator (see chapter Engine electrical equipment).
Lighting fixtures not working
Bulb burnt out (s) (see chapter Onboard electrical equipment).
Oxidized lamp base or socket contacts (see chapter Onboard electrical equipment).
Blown fuse (see chapter Onboard electrical equipment).
Faulty relay (see chapter Onboard electrical equipment).
Damaged wiring or loose terminal connections (see chapter Onboard electrical equipment).
Faulty switch (see chapter Onboard electrical equipment).
Violated the accuracy or stability of instrument readings
Readings increase with engine RPM
Faulty voltage regulator (see chapter Onboard electrical equipment).
No Fuel Flow or Temperature Sensor Readings
Faulty sensor (see chapter Cooling, heating systems or Power systems).
Broken wiring (see chapter Onboard electrical equipment).
Meter defective (see chapter Onboard electrical equipment).
The fuel flow or temperature sensor constantly gives the maximum reading
Faulty sensor (see chapters Cooling, heating systems and Power systems).
Broken wiring (see chapter Onboard electrical equipment).
Meter defective (see chapter Onboard electrical equipment).
Horn malfunction
The horn constantly beeps
The horn button is stuck pressed, (see chapter Onboard electrical equipment).
There is a short to ground in the electrical wiring of the horn (see chapter Onboard electrical equipment).
Klaxon does not sound
Blown fuse (see chapter Onboard electrical equipment).
Broken wiring or loose terminal connections (see chapter Onboard electrical equipment).
Faulty horn (see chapter Onboard electrical equipment).
Klaxon gives out too weak or unstable signal
Loose terminal connections (see chapter Onboard electrical equipment).
Loose horn sirens (see chapter Onboard electrical equipment).
Faulty horn (see chapter Onboard electrical equipment).
Windshield wipers malfunction (front/rear)
Windshield wipers do not move or move too slowly
brushes "stuck" to the glass, or the drive rod is jammed/deformed (see chapters Current service and Onboard electrical equipment).
Blown fuse (see chapter Onboard electrical equipment).
Broken wiring or loose terminal connections (see chapter Onboard electrical equipment).
Faulty relay (see chapter Onboard electrical equipment).
Faulty drive motor (see chapter Onboard electrical equipment).
Excessively large/small brush span
Wiper arms not properly seated on spindles (see chapter Current service).
Worn drive mechanism (see chapter Onboard electrical equipment).
Loose motor or drive assembly (see chapter Onboard electrical equipment).
Brushes do not clean glass
Worn rubber working elements (see chapter Onboard electrical equipment).
Lever extension springs broken or levers stuck on axles (see chapter Onboard electrical equipment).
Windshield washer fluid does not contain the appropriate cleaner needed to remove road film (see chapter Current service).
Windshield washers malfunction (front/rear)
One or more nozzles not working
The patency of the nozzle is broken (see chapter Current service).
Supply hose disconnected or obstructed due to blockage or kinks (see chapter Onboard electrical equipment).
Not enough liquid in the reservoir (see chapter Current service).
Fluid pump not working
Broken wiring or loose terminal connections (see chapter Onboard electrical equipment).
Blown fuse (see chapter Onboard electrical equipment).
Faulty switch (see chapter Onboard electrical equipment).
Faulty pump (see chapter Onboard electrical equipment).
Liquid starts to flow with a delay after the pump is turned on
Defective one-way valve in the supply hose (see chapter Onboard electrical equipment).
Functioning of the electric drive of windows is broken
Glasses only move in one direction
Faulty switch (see chapter Onboard electrical equipment).
Glass moves too slowly
Regulator damaged, stuck, or needs lubrication (see chapter Body and trim).
Internal components of the door or its interior upholstery interfere with the functioning of the regulator (see chapter Body and trim).
Faulty electric motor (see chapter Body and trim).
Glass does not move at all
Blown fuse (see chapter Onboard electrical equipment).
Faulty relay (see chapter Onboard electrical equipment).
Broken wiring or loose terminal connections (see chapter Onboard electrical equipment).
Faulty electric motor (see chapter Onboard electrical equipment).
Functioning of a single lock is broken
The system doesn't work at all
Blown fuse (see chapter Onboard electrical equipment).
Faulty relay (see chapter Onboard electrical equipment).
Broken wiring or loose terminal connections (see chapter Onboard electrical equipment).
Faulty control unit (see chapter Body and trim).
The latch locks but does not release, or vice versa
Broken or disconnected actuator rods or levers (see chapter Body and trim).
Faulty relay (see chapter Onboard electrical equipment).
Faulty control unit (see chapter Body and trim).
Faulty lock mechanism (see chapter Body and trim).
One of the control motors/electromagnets does not work
Broken wiring or loose terminal connections (see chapter Onboard electrical equipment).
Faulty actuator assembly (see chapter Body and trim).
Broken, jammed, or disconnected actuator rods or levers (see chapter Body and trim).
Faulty lock mechanism (see chapter Body and trim).