For vehicles with a diesel engine, the fuel system and the preheating system should be checked.
For vehicles with a carburetor, the carburetor should also be checked for serviceability and adjustment.
The engine does not start well, although the starter cranks without difficulty
Ignition system malfunction
- Blown fuse
- Spark plug defect
- Presence of leakage currents on high voltage wires
- Loose high voltage wire lugs or wire contacts
- Incorrectly adjusted gap of the ignition distributor
- Incorrectly set ignition timing
- Ignition coil defect
- Defect of the slider or cover of the ignition distributor
- Noise suppressor defect
Fuel system malfunction
- No fuel in the tank
- Fuel filter dirty
- Clogged fuel line or fuel hose
- Faulty fuel pump
- Carburetor throttle defect
- Defective float or float chamber of the carburetor
- K Faulty carburetor solenoid shut-off valve
- Incorrect carburetor adjustment
Low compression in the cylinders
- Spark plugs are tightened to the wrong torque or their seals are defective
- Loss of pressure due to leaking valve seats
- Valve stem stuck
- Weak or damaged valve springs
- Cylinder head gasket defect
- Stuck or broken piston ring
- Wear of pistons, rings or cylinders
- Incorrectly set valve clearance
Other reasons
- Rupture of the timing belt of the gas distribution mechanism
- Defective crankcase ventilation valve
Remedy
- Replace fuse
- Correct the gap between the electrodes, clean the candles or replace them
- Replace high voltage wire
- Adjust the gap of the ignition distributor
- Adjust ignition timing Replace ignition coil
- Replace slider or distributor cap
- Install a New Noise Diode
- Refuel
- Replace fuel filter
- Clean the fuel lines
- Replace fuel pump
- Check damper and replace if necessary
- Adjust float position
- Check valve and replace if necessary
- Adjust the carburetor
- Tighten spark plugs to specified torque or replace defective gasket
- Remove the cylinder head and lap the valves
- Lap the valve guide and stem
- Replace springs
- Replace the cylinder head gasket or repair the head
- Replace damaged piston ring
- Install oversize piston
- Adjust valve clearances
- Install a new toothed belt, checking the condition of the valves and pistons
- Replace valve
The engine does not run at full power (power drop)
Ignition system malfunction
- Ignition timing incorrectly adjusted
- Faulty spark plugs
- Deterioration of contacts of the distributor of ignition
- Leakage currents on high voltage wires or loosening of their fit
Fuel system malfunction
- Clogged fuel line or fuel hose
- Clogged fuel filter
- Air filter clogged
- Intake manifold or carburetor gasket burnt out and additional air is being sucked in
- Carburetor damper defect
- Fuel pump malfunction
- Clogged carburetor jets
Low compression (see above)
Other reasons
- Loose or broken low pressure hose
- Exhaust gas recirculation valve defective
- Parking brake lever applied or «sticking» brake pads
- Clutch slippage
Remedy
- Adjust ignition timing
- Check spark plugs and replace if necessary
- Check the condition of the terminals and the distributor slider. Replace if necessary.
- Check wires and replace if necessary
- Clean the fuel lines
- Replace fuel filter
- Replace or clean the air filter
- Check damper
- K Replace fuel pump
- Clean the jets
- Check the fit and condition of the hose. Replace hose if necessary.
- Check valve. Replace if necessary. Release the parking brake lever or check the pads.
- Adjust the position of the clutch disc or replace it.
Excessive idle speed or engine stall at idle
Ignition system malfunction
- Spark plug defect
- Leakage currents or loosening of the high voltage wire
- Deterioration of contacts of the distributor of ignition
- Incorrectly adjusted ignition timing
- Crack on the cover of the ignition distributor and leakage currents
Faulty fuel system
- Not enough fuel in the tank
- Air filter clogged
- Leakage in the intake manifold, ignition distributor or cylinder head
- Clogged carburetor jets
- Incorrect position of the carburetor float
- Carburetor damper defect
- Defective carburetor check valve
Other
- Loose or broken low pressure hose
- Exhaust gas recirculation valve defective
- Defective crankcase ventilation valve
Remedy
- Check spark plugs and replace if necessary
- Check high voltage wires and replace if necessary
- Check the condition of the terminals and the distributor slider. Replace if necessary
- Adjust ignition timing
- Replace distributor cap
- Refuel
- Clean the air filter or replace the replacement filter element
- Check the condition of the gaskets and replace if necessary
- Clean the jets
- Adjust float position
- Check damper
- Replace check valve
- Check the fit and condition of the hose. Replace hose if necessary
- Check and replace valve if necessary
- Check and replace valve if necessary
Engine overheating
- Low coolant level
- Weak water pump belt
- Faulty thermostat
- Insufficient water pump delivery volume
- Ignition timing not adjusted
- Dirty or leaky radiator
- The engine is filled with oil that does not meet the specification
- Dirty oil filter or sump strainer
- Low oil level in the engine
- Bad oil pump
- Leakage of the lubrication system and leakage of engine oil
- Sticky brake pads
- Clutch slip
- Burnt-out cylinder head gasket
Remedy
- Add coolant to the expansion tank
- Adjust water pump drive belt tension
- Replace thermostat
- Replace water pump
- Adjust ignition timing
- Flush, repair or replace the radiator
- Drain engine oil and refill with new one of the correct specification
- Change oil filter or clean oil pickup screen
- Add engine oil
- Repair the leak
- Check the brake pads. Install new ones if necessary
- Adjust clutch or replace driven disc
- Install a new cylinder head gasket
Increased fuel consumption
Fuel system malfunction
- fuel leak
- Dirty air filter element
- Incorrect position of the carburetor float
- Carburetor damper defect
- Dirty carburetor jets
Ignition system malfunction
- Unadjusted ignition timing
- Leakage currents or loosening of the high voltage wire
- Spark plug defect
Other reasons
- Valve seat leakage
- Sticky brake pads
- Clutch slip
- Faulty thermostat
- Tire pressure not correct
- Faulty exhaust gas recirculation valve
Remedy
- Fix fuel leak
- Clean or replace the replacement filter element
- Repair or replace damper
- Adjust float position
- Clean the carburetor jets
- Adjust ignition timing
- Check high voltage wires and replace if necessary
- Clean or replace spark plugs
- Repair or replace valve seats
- Check the brake pads. Install new ones if necessary
- Adjust clutch or replace driven disc
- Replace thermostat
- Adjust tire pressure to correct
- Check valve and replace if necessary
Increased engine oil consumption
Leakage of engine oil due to leaks in the lubrication system
- Loose drain plug
- Loose oil pump bolts
- Rupture of the sealant layer that seals the oil pan
- Crankshaft oil seal defect
- Cylinder head cover gasket defect
- Weak oil filter
- Weak fit of the engine oil pressure sensor
- Cylinder head gasket defect
- Defective camshaft seals
Entry of engine oil into the combustion chambers
- Piston ring sticking
- Piston and piston ring wear
- Displacement of locks of piston rings
- Worn valve stems or oil seals
Remedy
- Tighten the drain plug and also tighten the oil pan bolts
- Remove the oil pan and apply a new layer of sealant
- Replace seals
- Replace seal
- Tighten the oil filter
- Tighten the sensor to the specified torque
- Install a new seal
- Replace seals
- Remove carbon deposits or replace piston rings
- Install oversize pistons
- Correct the position of the O-rings on the piston
- Replace valve stems or seals