Identifying and troubleshooting engine faults (Peugeot 605)

If the petrol engine does not start, then gradually narrow down the search for the fault. To start the petrol engine, two basic conditions must be met; the fuel-air mixture must enter the cylinders, and there must be a spark on the spark plugs. Therefore, first of all, you should check whether there is a fuel supply. Malfunctions of the engine control electronics can only be determined using special control and measuring devices.

For vehicles with a diesel engine, the fuel system and preheating system should be checked.

For cars with a carburetor, the carburetor should also be checked for proper operation and adjustment.

The engine starts poorly, although it turns over with the starter without difficulty

Ignition system malfunction

• The fuse has blown
• Spark plug defect
• Presence of leakage currents on high voltage wires
• Loose fit of high voltage wire tips or wire contacts
• Incorrectly adjusted distributor gap
• Incorrectly set ignition timing
• Ignition coil defective
• Defective rotor or distributor cap
• Defective interference suppressor

Fuel system malfunction

• No fuel in the tank
• The fuel filter is dirty
• The fuel line or fuel hose is clogged
• The fuel pump is faulty
• Carburetor throttle valve defect
• Defective float or float chamber of the carburetor
• K The electromagnetic shut-off valve of the carburetor is faulty
• Incorrect carburetor adjustment

Low compression in cylinders

• The spark plugs are tightened with the wrong torque or their sealing gaskets are defective
• Pressure loss due to leaky valve seats
• Valve stem stuck
• Weak or damaged valve springs
• Cylinder head gasket defect
• Piston ring stuck or broken
• Worn pistons, rings or cylinders
• Incorrectly set valve clearance

Other reasons

• Timing belt rupture of the gas distribution mechanism
• Crankcase ventilation valve defect

Method of elimination

• Replace the fuse
• Adjust the gap between the electrodes, clean the spark plugs or replace them
• Replace the high voltage wire
• Adjust the distributor gap
• Adjust the ignition timing Replace the ignition coil
• Replace the rotor or distributor cap
• Install a new noise suppression diode
• Fill up
• Replace the fuel filter
• Clean the fuel lines
• Replace the fuel pump
• Check the damper and replace it if necessary
• Adjust the float position
• Check the valve and replace if necessary
• Adjust the carburetor
• Tighten the spark plugs to the specified torque or replace the defective gasket
• Remove the cylinder head and grind the valves
• Grind the guide and valve stem
• Replace the springs
• Replace the cylinder head gasket or repair the head
• Replace the damaged piston ring
• Install a piston of oversize
• Adjust the valve clearances
• Install a new timing belt, checking the condition of the valves and pistons
• Replace the valve

The engine does not operate at full power (power drop)

Ignition system malfunction

• The ignition timing is incorrectly adjusted
• The spark plugs are faulty
• Wear of ignition distributor contacts
• Leakage currents on high voltage wires or loosening of their connection

Fuel system malfunction

• The fuel line or fuel hose is clogged
• The fuel filter is clogged
• The air filter is clogged
• The intake manifold or carburetor seal has burned out and additional air is being sucked in
• Carburetor flap defect
• Fuel pump malfunction
• The carburetor jets are clogged

Low compression (see above)

Other reasons

• Loose or broken low pressure hose
• EGR valve defect
• Tightened parking brake lever or "sticking" brake pads
• Clutch slave disc slippage

Method of elimination

• Adjust the ignition timing
• Check the spark plugs and replace them if necessary
• Check the condition of the terminals and distributor rotor. Replace if necessary.
• Check the wires and replace if necessary
• Clean the fuel lines
• Replace the fuel filter
• Replace or clean the air filter
• Check the damper
• K Replace the fuel pump
• Clean the jets
• Check the fit and condition of the hose. Replace the hose if necessary.
• Check the valve. Replace if necessary. Release the parking brake lever or check the pads.
• Adjust the position of the clutch slave disc or replace it.

High idle speed or engine stalling at idle

Ignition system malfunction

• Spark plug defect
• Leakage currents or loosening of the high voltage wire seat
• Wear of ignition distributor contacts
• Incorrectly adjusted ignition timing
• Crack in the distributor cap and leakage currents

The fuel system is faulty

• Not enough fuel in the tank
• The air filter is clogged
• Leakage in the intake manifold, distributor or cylinder head
• The carburetor jets are clogged
• Incorrect position of the carburetor float
• Carburetor flap defect
• Defective carburetor shut-off valve

Others

• Loose or broken low pressure hose
• EGR valve defect
• Crankcase ventilation valve defect

Method of elimination

• Check the spark plugs and replace them if necessary
• Check high voltage wires and replace if necessary
• Check the condition of the terminals and distributor rotor. Replace if necessary
• Adjust the ignition timing
• Replace the distributor cap
• Fill up
• Clean the air filter or replace the replaceable filter element
• Check the condition of the sealing gaskets and replace them if necessary
• Clean the jets
• Adjust the float position
• Check the damper
• Replace the shut-off valve
• Check the fit and condition of the hose. Replace the hose if necessary
• Check and replace the valve if necessary
• Check and replace the valve if necessary

Engine overheating

• Low coolant level
• The water pump belt is loose
• Thermostat is faulty
• Insufficient water pump flow
• The ignition timing is not adjusted
• Dirty or leaky radiator
• The engine is filled with oil that does not meet the specification
• The oil filter or the oil pickup mesh filter in the pan is dirty
• Low engine oil level
• The oil pump is not working properly
• Leakage in the lubrication system and engine oil leakage
• Brake pads sticking
• Clutch slippage
• Burnt out cylinder head gasket

Method of elimination

• Add coolant to the expansion tank
• Adjust the tension of the water pump drive belt
• Replace Thermostat
• Replace the water pump
• Adjust the ignition timing
• Flush, repair or replace your radiator
• Drain the engine oil and fill with new oil of the appropriate specification
• Replace the oil filter or clean the oil pickup screen
• Add engine oil
• Fix the leak
• Check the brake pads. Install new ones if necessary
• Adjust the clutch or replace the driven disc
• Install a new cylinder head gasket

Increased fuel consumption

Fuel system malfunction

• Fuel leak
• Dirty replacement air filter element
• Incorrect position of the carburetor float
• Carburetor flap defect
• The carburetor jets are dirty

Ignition system malfunction

• Ignition timing not adjusted
• Leakage currents or loosening of the high voltage wire seat
• Spark plug defect

Other reasons

• Valve seat leakage
• Brake pads sticking
• Clutch slippage
• Thermostat is faulty
• The tire pressure is not correct
• The EGR valve is faulty

Method of elimination

• Fix the fuel leak
• Clean or replace the replaceable filter element
• Repair or replace the damper
• Adjust the float position
• Clean the carburetor jets
• Adjust the 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 the clutch or replace the driven disc
• Replace Thermostat
• Adjust the tire pressure to the correct level
• Check the valve and replace it if necessary

Increased engine oil consumption

Engine oil leak due to leaky lubrication system

• Loose drain plug
• Loose tightening of oil pump mounting bolts
• Rupture of the sealant layer that seals the oil pan
• Crankshaft oil seal defect
• Cylinder head cover gasket defect
• Loose oil filter tightening
• Loose fit of engine oil pressure sensor
• Cylinder head gasket defect
• Camshaft seal defect

Engine oil entering combustion chambers

• Sticking piston ring
• Wear of piston and piston rings
• Piston ring lock offset
• Worn valve stems or valve stem seals

Method of elimination

• Tighten the drain plug and tighten the oil pan mounting bolts
• Remove the oil pan and apply a new coat of sealant
• Replace the seals
• Replace the sealing gasket
• Tighten the oil filter
• Tighten the sensor to the specified torque
• Install a new sealing gasket
• Replace the seals
• Remove carbon deposits or replace piston rings
• Install oversize pistons
• Adjust the position of the sealing rings on the piston
• Replace valve stems or valve stem seals