Part A: Carburetor Engines
Symptom/Cause (causes)
Smell of gasoline when turning off the engine/
- Fuel lines or fittings are leaking
- The fuel tank is leaking.
Smell of gasoline when engine is idling/
- The fuel line fittings between the pump and the carburetor are leaking
- Fuel overflows from the float chamber due to an incorrectly adjusted level, a faulty needle valve, or a leaking float.
Excessive fuel consumption for reasons not related to leaks or float chamber/
- Jets are worn out
- Mixture too rich
- Any of the carburetor mechanisms is jammed
- The air filter is dirty
- The thermostat mechanism of the air cleaner is stuck.
Problems starting the engine, rough running, reduced engine power, spontaneous shutdown/
- One or more jets are completely or partially clogged
- The fuel level in the float chamber is too low or the needle valve is stuck
- Fuel pump is not delivering enough fuel. Solenoid shut-off valve is faulty (if installed)
- The induction system sucks in air
- The strainer on the carburetor inlet fuel line is clogged.
Problems starting a cold engine/
- Manual or automatic suction is poorly adjusted
- The automatic choke was not reset before starting the engine.
Problems starting a warm engine/
- Automatic choke is poorly adjusted
- Before starting the engine, the gas pedal was pressed several times
- Steam plug (especially likely in hot weather or at high altitudes above sea level).
The engine does not respond well to pressing the pedal
- Accelerator pump faulty
- The jet is clogged (jets)
- The throttle cable is weak.
Idle speed drops when the engine is warm/
- Temperature compensator faulty
- The fuel pump has overheated.
Part B: Injection engines
Symptom/Cause (causes)
Problems starting a cold engine/
- Fuel pump faulty
- Fuel line or filter clogged
- Auxiliary air valve faulty
- Temperature sensor faulty
- Vacuum system leaks.
Problems starting a warm engine/
- Air filter clogged
- Fuel pump faulty
- Vacuum system leaks.
Excessive fuel consumption/
- Excessive fuel pressure
- Temperature sensor faulty
- Air flow sensor faulty
- Vacuum system leaks.
Rough idle /
- The air intake system allows air to pass through
- The composition of the mixture is incorrectly adjusted
- Throttle switch poorly adjusted
- The electronic control unit plug has come loose
- The injector is leaking (injectors).
Poorly regulated (too high) idle speed/
- Auxiliary air valve does not close.
Visitor comments