Engine malfunctions

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Engine does not rotate when trying to start


  • Loose or corroded battery contacts (Chapter 5).
  • The battery is empty or defective (Chapter 5).
  • Open, disconnected or loose contacts in the starter circuit (Chapter 5).
  • Faulty starter solenoid or switch (Chapter 5).
  • Faulty starter (Chapter 5).
  • Electric starter gear or flywheel teeth loose or broken (Chapter 5).
  • Open or disconnected motor ground jumper (Chapter 5).
  • Automatic transmission in gears other than "Park" or "Neutral" or selector failure (Chapter 7B).

Engine turns over but does not start


  • Empty fuel tank.
  • Battery low (motor rotates slowly) (Chapter 5).
  • Loose or corroded battery contacts (Chapter 5).
  • Ignition system components defective or damp - (Chapters 1, 5).
  • Open, disconnected or loose contacts in the ignition circuit (Chapters 1, 5).
  • Worn, defective or incorrect spark plug gap setting (Chapter 1).
  • Serious mechanical failure (e.g. camshaft drive) (Chapter 2A).


Engine won't start when cold


  • Low battery (Chapter 5).
  • Loose or corroded battery contacts (Chapter 5).
  • Worn, defective or incorrect spark plug gap setting (Chapter 1).
  • Ignition system malfunction (Chapters 1, 5).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Low compression in the cylinders (Chapter 2A).


Engine won't start when hot


  • Dirty or clogged air filter element (Chapter 1).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Low compression in the cylinders (Chapter 2A).
  • Malfunction of hydraulic valve clearance compensators (Chapter 2A).


Excessive noise when the starter is running or jerking when it engages


  • Starter gear or flywheel teeth loose or broken (Chapter 5).
  • Loose starter mounting bolts (Chapter 5). Internal starter components worn or damaged (Chapter 5).


Engine starts and dies immediately


  • Open or loose contacts in the ignition circuit (Chapters 1, 5).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Intake manifold vacuum leak (Chapter 1, 4, 6).


Engine idling erratically


  • Idle speed control valve malfunction (Chapter 4).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Dirty or clogged air filter element (Chapter 1).
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).
  • Worn, defective or incorrect spark plug gap setting (Chapter 1).
  • Malfunction of hydraulic valve clearance compensators (Chapter 2A).
  • Unequal or low compression in the engine cylinders (Chapter 2).
  • Camshaft lobes wear (Chapter 2).
  • Incorrect setting of the toothed belt tension of the timing mechanism (Chapter 2A).


Ignition failures when the engine is idling


  • Worn, defective or incorrect spark plug gap setting (Chapter 1).
  • Malfunction of high-voltage wires of spark plugs (Chapter 1).
  • Idle speed control valve malfunction (Chapter 4).
  • Incorrect ignition timing (Chapters 5, 6).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).
  • Malfunction of hydraulic valve clearance compensators (Chapter 2A).
  • Unequal or low compression in the engine cylinders (Chapter 2).
  • Disconnection, leakage, or destruction of rubber crankcase breather hoses (Chapters 1, 6).


Engine ignition failures in the operating speed range


  • Fuel filter clogged (Chapter 1).
  • Malfunction or reduced pressure of delivery of the fuel pump (Chapter 4).
  • Clogged fuel tank vent or kinked fuel line (Chapter 4).
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).
  • Worn, defective or incorrect spark plug gap setting (Chapter 1).
  • Malfunction of high-voltage wires of spark plugs (Chapter 1).
  • Ignition coil failure (Chapter 5),
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Unequal or low compression in the engine cylinders (Chapter 2A).


The engine runs erratically during acceleration


  • Worn, defective or incorrect spark plug gap setting (Chapter 1).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).


Engine stalls


  • Idle speed control valve malfunction (Chapter 4).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6),
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).
  • Fuel filter clogged (Chapter 1).
  • Malfunction or reduced pressure of delivery of the fuel pump (Chapter 4).
  • Clogged fuel tank vent or kinked fuel line (Chapter 4).


Insufficient engine power


  • Incorrect ignition timing (Chapters 5, 6).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Incorrect installation or incorrect tension of the timing belt (Chapter 2A).
  • Fuel filter clogged (Chapter 1).
  • Malfunction or reduced pressure of delivery of the fuel pump (Chapter 4).
  • Unequal or low compression in the engine cylinders (Chapter 2A).
  • Worn, defective or incorrect spark plug gap setting (Chapter 1).
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).
  • Jamming brakes (Chapters 1 and 9).
  • Clutch slip (Chapter 8).
  • Incorrect fluid level in automatic transmission (Chapter 1).


Motor continues to rotate after shutdown


  • Excessively high idle speed (Chapters 4, 6).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Excessive contamination of internal engine parts by fuel residues (Chapter 2A).
  • Engine operation at elevated temperatures (Chapter 3).


Backfires in the engine


  • Incorrect ignition timing (Chapters 5, 6).
  • Malfunction of the engine management system (Chapters 1, 4, 5, 6).
  • Incorrect installation or incorrect tension of the timing belt (Chapter 2A).
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).


When the engine is running, the low oil pressure indicator is on


  • Low oil level or use of non-regulated type oil (Chapter 1).
  • Faulty oil pressure sensor (Chapter 2A).
  • Worn engine bearings and/or oil pump (Chapter 2).
  • Engine operation at elevated temperatures (Chapter 3).
  • Defective oil pressure relief valve (Chapter 2A),
  • Intake pipe strainer clogged (Chapter 2A).


Noises in the engine


Preignition (detonation) or knocking sound when accelerating or under load


  • Incorrect ignition timing (Chapters 5, 6).
  • Fuel of the wrong brand (Chapter 4).
  • Vacuum leak in the intake manifold or hoses connected to it (Chapter 1, 4, 6).
  • Excessive contamination of internal engine parts by fuel residues (Chapter 2A).


Whistling or wheezing noises


  • Leakage through intake manifold gasket (Chapter 2A).
  • Leakage at the exhaust manifold gasket or exhaust manifold joint (Chapter 1, 2A, 4).
  • Vacuum hose leak (Chapters 1, 4, 6, 9).
  • Breakdown of the cylinder head gasket (Chapter 2A).


Knocking or rattling noises


  • Malfunction of hydraulic valve clearance compensators (Chapter 2A).
  • Valve actuator or camshaft wear (Chapter 2A).
  • Worn toothed belt or tensioner (Chapter 2A).
  • Malfunction in auxiliary units (cooling system pump, generator, etc.) (Chapters 3, 5 etc.).


Bumps or thuds


  • Wear of connecting rod bearings (regular heavy knocking, with possible weakening under load) (Chapter 2B).
  • Wear of main bearings (rattling and knocking, with possible weakening under load) (Chapter 2B).
  • Piston shift (heard on a cold engine) (Chapter 2B).
  • Malfunction in auxiliary units (cooling system pump, generator, etc.) (Chapters Chapters 3, 5 etc.).







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