- The battery terminals are loose or corroded ("Weekly checks").
- Discharged or defective battery (Section 4A).
- The wiring in the starter circuit is broken or disconnected (Section 4A).
- Defective starter traction relay or switch (Section 4A).
- Defective starter (Section 4A).
- The starter gear or flywheel ring gear teeth are defective (Section 1).
- The engine ground strap is broken or disconnected (Section 4A).
The engine turns over but does not start
- The fuel tank is empty.
- The battery is discharged (the engine is turning slowly) (Section 4A).
- The battery terminals are loose or corroded.
- Defective pre-heating system - diesel models (Section 4B).
- Fuel shut-off valve not working - diesel models (Section FOR).
- Air in the Fuel System - Diesel Models (Section 3A).
- Serious mechanical failure (for example, camshaft drive)
Difficulty starting a cold engine
- Discharged battery (Section 4A).
- Battery terminals are loose or corroded
- Defective pre-heating system - diesel models
- High idle speed valve not adjusted correctly - diesel models.
- Low compression in engine cylinders (Section 1).
Excessive noise in the starter when turned on
- The starter gears or flywheel ring teeth are damaged (Sections 1 and 4A).
- Starter mounting bolts are loose or missing (Section 4A).
- The internal components of the starter are worn or damaged (Section 4A).
Unstable engine idle speed
- The air filter element is clogged.
- Uneven or low compression in engine cylinders (Section 1).
- The camshaft cams are worn out (Section 1).
- Incorrect tension of the timing belt.
- Defective injector - diesel models (Section FOR).
Misfires at idle speed
- Defective injector - diesel models (Section FOR).
- Different or low compression in engine cylinders (Section 1).
- Disconnected, leaking or kinked crankcase ventilation hoses (Section ZV).
Misfires at all engine speeds
- The fuel filter is clogged.
- Defective injector - diesel models (Section FOR).
- Uneven or low compression in engine cylinders (Section 1).
- Fuel system damage (Section FOR).
Engine shakes when accelerating
- Defective injector - diesel models (Section FOR).
The engine stalls
- The fuel filter is clogged.
- Defective injector - diesel models (Section FOR).
The engine does not develop power
- Incorrect tension of the timing belt (Section 1).
- The fuel filter is clogged.
- Uneven or low compression in engine cylinders (Section 1).
- Fuel system damage (Section FOR).
- Defective injector - diesel models (Section FOR).
- Fuel pump faulty - diesel models (Section FOR).
- Brakes sticking (Section 9).
- Clutch slippage (Section 5).
The oil pressure warning light is on
- Low oil level or wrong type of oil ("Weekly checks").
- Defective oil pressure sensor (Section 4A).
- The engine bearings and/or oil pump are worn out (Section 1).
- High engine operating temperature (Section 2).
- The oil pump bypass valve is faulty (Section 1).
- The mesh filter of the oil intake tube is clogged (Section 1).
The engine continues to run after being turned off
- Excessive increase in carbon content in the engine (Section 1).
- High engine operating temperature (Section 2).
- The fuel shut-off valve on the pump is faulty - diesel models (Section FOR).
Whistling or wheezing noises from the engine
- Leaking exhaust manifold gasket or downpipe coupling
- The cylinder head gasket is broken (Section 1).
Fluid leaking and rattling noises
- The valve mechanism or camshaft is worn out (Section 1).
- Damage to auxiliary components (water pump, generator, etc.)
Detonation or dull noises
- The lower connecting rod head bearings are worn out (regular heavy detonation, possibly less under load) (Section 1).
- The main bearings are worn out (rumble and detonation, worsening under load)
- Piston wear (especially noticeable on a cold engine) (Section 1).
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