Fuel vapor recovery system diagram
Scheme of the system for monitoring and reducing toxicity of exhaust gases and capturing fuel vapors of the 1.6 liter engine with an on-board diagnostics system
1 – control relay; 2 – ECM amplifier; 3 – ignition switch; 4 – ignition coil; 5 – spark plug; 6 – camshaft position sensor; 7 – crankcase ventilation valve; 8 – air flow meter and air temperature sensor; 9 – acceleration sensor; 10 – ECM; 11 – air filter; 12 – idle speed control valve; 13 – throttle position sensor; 14 – activated carbon canister cleaning valve; 15 – canister with activated carbon; 16 – fuel tank; 17 – muffler; 18 – crankshaft angle sensor; 19 – knock sensor; 20 – coolant temperature sensor; 21 – oxygen sensor; 22 – catalytic converter; 23 – oxygen sensor
Scheme of the system for monitoring and reducing toxicity of exhaust gases and capturing fuel vapors of 1.6/1.8/2.0 l engines (leaded fuel)
1 – control relay; 2 – ECM amplifier; 3 – ignition switch; 4 – ignition coil; 5 – spark plug; 6 – camshaft position sensor; 7 – crankcase ventilation valve; 8 – air flow meter and air temperature sensor; 9 – ECM; 10 – idle speed control system valve; 11 – air filter; 12 – throttle position sensor; 13 – activated carbon canister cleaning valve; 14 – canister with activated carbon; 15 – fuel tank; 16 – muffler; 17 – crankshaft angle sensor; 18 – knock sensor; 19 – coolant temperature sensor
The fuel vapor recovery system prevents fuel vapor from evaporating into the atmosphere from the fuel tank, thereby preventing the formation of photochemical smog.
Fuel vapors are accumulated in a canister with activated carbon. When the engine is running, the electronic control unit opens the valve and fuel vapors enter the engine, where they are burned.
The control valve is used to control the fuel vapor pressure in the fuel tank.
Examination
1. Disconnect the vacuum hose from the throttle body and connect a vacuum pump with a vacuum hose in its place.
2. Check the following parameters with the engine cold and the coolant temperature below 60°C and with the engine hot and the coolant temperature above 80°C.
Cold engine
Engine operating mode | Underpressure | Result |
| Idling | 50 kPa | Vacuum is maintained |
| 3000 min⁻¹ |
Hot engine
Engine operating mode | Underpressure | Result |
| Idling | 50 kPa | Vacuum is maintained |
| Within 3 minutes after increasing the rotation speed to 3000 min⁻¹ | Attempt to change rarefaction | There is no vacuum |
| After 3 minutes of increasing the rotation speed to 3000 min⁻¹ | 50 kPa | The vacuum is maintained for a short time, after which it disappears |