Attention. Under normal operating conditions, the opening for communication with the atmosphere should be open.
Communication with the atmosphere of the fuel tank is carried out through the adsorber (vapor trap). Gasoline vapors are retained by activated carbon contained in the adsorber. Gasoline vapors from the adsorber enter the engine, where they burn out. To do this, the absorber is connected to the intake manifold using a solenoid valve. The solenoid valve is located on the mudguard cup.
The principle of operation of the solenoid valve is to change the flow area depending on the signal of the degree of cyclic opening coming from the injection computer.
The change in the flow area of the fuel vapor channel in the solenoid valve occurs due to the balance between the magnetic field created by the winding supply voltage and the force of the return spring, which ensures the closing of the solenoid valve.
Canister Purge Conditions
The control signal to the canister purge solenoid valve is supplied through contact C-E1 of the computer connector under the following conditions:
- coolant temperature above 55°C;
- air temperature above 10°С;
- the engine is not in idle mode;
- the specified load threshold has been reached;
- throttle position sensor is not in position «idling».
When diagnosing with «on-board diagnostic system» adsorber purge is not permitted.
The canister purge solenoid valve cycling degree can be determined using a scan tool by reading parameter PR102.
The solenoid valve is closed when the parameter value is below 1.2%.
Functional diagram and arrangement of elements of the toxicity reduction system:
1 - intake manifold;
2 - solenoid valve for adsorber purge;
3 - adsorber;
4 - fuel tank;
5 - opening of communication with the atmosphere;
6 - check valve (only on M4R engine);
7 - solenoid valve purge adsorber (K4M);
8 - canister purge solenoid valve (M4R);
9 - adsorber;
10 - pipeline for supplying gasoline vapor from the fuel tank;
11 - pipeline for supplying gasoline vapors to the intake manifold;
12 - tube communication with the atmosphere of the adsorber.