Engine does not turn over with starter
- Low battery
- Loose or corroded battery terminals
- Loose contacts on the starter solenoid terminals
- Loose or damaged engine/gearbox ground wire
- Faulty starter
Engine cranks normally but won't start
- Wrong start procedure
- Injection pump cut-off solenoid is defective or there is a break in its wiring
- The fuel contains resins and paraffin (only occurs in very cold weather)
- Broken timing belt Fuel system malfunction
- Bad compression (see below)
- The synchronization of the injection pump operation is broken
Rough idle
- Fuel system malfunction
- Valve clearances incorrectly adjusted
- Burnt valves
- Broken cylinder head gasket
Bad compression
- Burnt valves
- Too small valve clearances
- Broken cylinder head gasket
- Worn piston rings/cylinders
- Cracks in the cylinder head or block
The engine does not develop the required power
- Bad compression (see above)
- The synchronization of the injection pump operation is broken
- Worn or dirty injectors
- Clogged air filter
Excess oil consumption
- Leaking camshaft or crankshaft seals
- Worn piston rings/cylinders (the sign is smoky exhaust)
- External oil leaks
Unusual engine noises
- Peripheral hardware failure (e.g. water pump or generator)
- Worn or damaged timing belt or alternator drive belt
- Broken piston ring (rings)
- Worn connecting rod bearings (noise increases without load)
- Worn main bearings (noise increases under load)
- Injector or injection pump malfunction (see chapter 3)
Smoky exhaust
- Engine burns oil (exhaust has a blue tint)
- Fuel system malfunction