9.4. System retsirkulyatsiya (EGR system)
1. It is intended for decrease in the content of oxides of nitrogen in exhaust gases at the expense of decrease in temperature of combustion of gas mixture. It is reached by the redirection of a part of these gases via the retsirkulyatsiya valve in soaking-up collector. The design of the valve depends on type of transmission and expected service conditions of the car in this region. Refusal of this system influences operation of the engine, causing unstable work idling and on small speeds of movement, "failures" at dispersals. The system consists of the valve of a retsirkulyatsiya and valves operating it (or pneumodistributors). On a part of cars operation of the valve of a retsirkulyatsiya the differential valve (Vrtklapan) operates.
2. The system is established on 4цилиндровых engines of cars of 198788 g of century and on V6 engines since 1987. Work of system the processor ECU block which is a part of processor system ECCS of the car operates. The valve of a retsirkulyatsiya is open at engine start-up, on the cold engine, on turns above 3200
1.5б Scheme of distributing of vacuum highways of system of purification of exhaust gases
3.3 The retsirkulyatsiya valve on VS engines is mounted behind the butterfly valve case on a soaking-up collector of rpm or 900 rpm are lower. In other conditions the valve is closed.
Check of the valve of a retsirkulyatsiya
3. Find the valve (photo).
4. Check freedom of moving of a diaphragm, having submitted it up (photo). When jamming diaphragm the valve replace.
5. Start the engine and close the valve by hand, having pressed on a diaphragm (dress gloves). The engine should lose turns and even to decay. If turns of the engine do not change, check a condition of a tube of selection of exhaust gases. If the return valve is provided, exclude it, having connected a hose the dempferny valve and the retsirkulyatsiya valve. Warm up the engine and finish turns to 20002500 about/minute. Disconnect from the retsirkulyatsiya valve a vacuum hose, the diaphragm should be displaced slowly down in process of increase of turns. Attach a hose, in process of decrease in turns the diaphragm should be displaced slowly down.
6. If the diaphragm does not move, check depression on the valve. For this purpose disconnect a vacuum hose on which depression should be felt. If depression is present, replace the retsirkulyatsiya valve. Otherwise check a hose condition, serviceability of the dempferny valve.
Check of the control differential pneumovalve (valve VRT)
7. Disconnect vacuum hoses in the top part of the valve.
8. Remove the valve. Muffle one of unions and try to create depression via other union if depression manages to be created, the valve is faulty (air should take place freely in the suction direction). Create pressure on the union in the lower part of the valve, thus air should not pass through the vacuum union. Otherwise the valve replace. Before installation of the valve blow hoses.
3.4 Check of a diaphragm of the valve of a retsirkulyatsiya
Check of the vacuum distributive valve (valve TVV)
Attention! On 4цилиндровых injector engines the distributive valve is mounted
in a forward part of a soaking-up collector.
9. On the cold engine disconnect a vacuum hose on the retsirkulyatsiya valve, start the engine and check depression increase. If depression accrues immediately, the TW valve replace. If on the heated-up engine depression is absent, check a condition of hoses. If hoses are serviceable, the TW valve replace.
Check of the dempferny valve
10. Remove the valve and blow from connection with the retsirkulyatsiya valve, air should pass freely. Air should pass in an opposite direction hardly. Otherwise the valve replace.
Check of the gate-type solenoidal valve of a retsirkulyatsiya
11. It is carried out in car-care center service as the special confided equipment is required.
Control differential pneumovalve (Vrtklapan)
12. Disconnect hoses, unscrew screws and raise the valve.
13. Disconnect a tube in the lower part of the valve and remove the valve.
14. Installation is carried out upside-down.
Vacuum distributor (TW)
15. Merge about 1 l of cooling liquid.
16. Designate and disconnect vacuum hoses.
17. Turn out the distributor.
18. Installation is carried out upside-down. Wrap the distributor on hermetic.
4.1а the Electromagnetic gate-type valve regulating depression in system of a dookisleniye