8.4. System of recirculation of the fulfilled gases (EGR) - the general information, check of a state and replacement of components

General information

 


For the purpose of decrease in issue in the atmosphere of oxides of nitrogen (NOH) the design of the engine provides withdrawal of a part of the fulfilled gases in the inlet pipeline via the EGR valve. Such admixture of the fulfilled gases to air-fuel mix leads to decrease in temperature of its combustion. The amount of the fulfilled gases mixed with the inlet pipeline is defined by several factors, such as: engine turns, depression depth in the pipeline, counter-pressure size in system of release, temperature of cooling liquid, the provision of a butterfly valve, etc.

All EGR systems which are a part valves have a vacuum design. Schemes of laying of vacuum hoses for concrete model are given in VECI label.

Check

EGR valve

 PERFORMANCE ORDER

1. Remove the EGR valve from the car. Make sure that freedom of the course of a plunger of valvate assembly is not limited to coal deposits. In case of need wash out the valve solvent.

2. Connect the manual vacuum pump to the valve and create depression of 508 mm of mercury in depth. (67 kPa). Also check tightness of assembly, - depression has to keep.

If the valve is equipped with two vacuum unions, check them serially.

3. On models 1990 ÷ of 1993 of the issue with a depth of depression less than 46 mm of mercury. (6 kPa) the valve has to remain closed (the purge of air through it should not be represented possible), opening of the valve happens with a depression depth more
216 mm of mercury. (28.7 kPa).
4. On models since 1994 of the issue, on the contrary, with a depth of depression less than 40 mm of mercury. the valve has to pass air, and more than 221 mm of mercury. - no.
5. The faulty valve is subject to replacement.


EGR temperature sensor (only Californian models)

 PERFORMANCE ORDER

1. The sensor of temperature of EGR is installed only on the models intended for operation in the State of California of the USA. The sensor traces temperature of EGR of the fulfilled gases passed via the valve of management and gives the relevant information (in the form of tension signals) on PCM. The break in a chain of the sensor leads to operation of the corresponding control lamp.
2. Remove EGR temperature sensor from the engine.

3. Lower the sensor in the container with hot water, there place the thermometer, - try not to assume that the sensor and the thermometer adjoined to vessel walls. Warming up water, measure sensor resistance at various values of temperature. Compare result to standard requirements (at a temperature of 50 °C resistance of the sensor has to make 60 ÷ 83 kOhm, at 100 °C - 11 ÷ 14 kOhm).

4. The faulty sensor is subject to replacement.


Thermal vacuum valve (TVV)

 PERFORMANCE ORDER

1. Previously having marked, disconnect a vacuum hose from TVV.

2. Connect the manual vacuum pump to a vacuum hose of the valve.

3. Create depression on TVV: at a temperature less than 50 °C the valve depression should not keep (the valve is open), switching happens at a temperature more than 80 °C.
4. The faulty valve is subject to replacement.


Check of port depression of EGR

 PERFORMANCE ORDER

1. Disconnect a vacuum hose from the throttle case. Connect the manual vacuum pump / vacuum gage to the released union.

2. Start the engine and, slowly lifting its turns, you watch instrument readings. On models 1990 ÷ 1993 depth of depression has to increase in proportion to the frequency of rotation of the engine, on models since 1994 of the issue, - to remain invariable.


Electromagnetic EGR valve

Models 1990 ÷ of 1990 of the issue.

 PERFORMANCE ORDER

1. Previously having marked, disconnect the vacuum hose marked with flavovirent strips from the electromagnetic EGR valve.
2. Disconnect an electrical wiring.

3. Connect to the released union on valvate assembly the manual vacuum pump. Create depression and check tightness of assembly at a tension given on it without that. In the first case depression has to keep reliably, in the second - no.

4. Measure valve resistance at a temperature of 20 °C, - the nominal rate makes 36 ÷ 44 Ohm.

5. The faulty valve is subject to replacement.


Models since 1994 of the issue.

 PERFORMANCE ORDER

1. Previously having marked, disconnect from the electromagnetic EGR valve the vacuum hose marked with flavovirent strips (in a yellow strip on models of 2.0 l with a turbo-supercharging, or in an ochroleucous strip on models of 2.4 l).
2. Disconnect an electrical wiring.

3. Connect the manual vacuum pump to the union A. Create depression and check tightness of assembly at a tension given on it without that. In the first case depression should not keep, in the second - has to.

4. Measure valve resistance at a temperature of 20 °C, - the nominal rate makes 36 ÷ 44 Ohm.
5. The faulty valve is subject to replacement.


Removal and installation of components

EGR valve

Removal

 PERFORMANCE ORDER

1. Disconnect a negative wire from the battery.

If the stereosystem established on the car is equipped with a security code before disconnecting the battery make sure that you have the correct combination for input of the audio system in action!

2. In case of need remove the air cleaner with inlet air ducts.
3. At the corresponding complete set (the Californian models) disconnect an electrical wiring from EGR temperature sensor.
4. Previously having marked, disconnect a vacuum hose from the EGR valve.

5. Turn out fixing bolts and remove the valve.

6. Carefully smooth out the interfaced surfaces, having completely removed from them all traces of material of old laying.
7. Check freedom of the course of a plunger of the valve, in case of need wash out assembly by solvent for the purpose of removal of coal deposits.


Installation

 PERFORMANCE ORDER

1. Having replaced sealing laying, put valvate assembly on the regular place on the engine.
2. Screw fixing bolts and tighten them with the required effort (10 ÷ 15 H • м: for models of 1.5 l, 1.6 l and 1.8 l; 15 ÷ 22 H • м: for models of 2.0 l; 22 H • м: for models of 2.4 l and 3.5 l; and 11 H • м: for models 3.0 l).
3. Connect a vacuum hose to the valve.
4. At the corresponding complete set connect an electrical wiring to EGR temperature sensor.
5. Establish assembly of the air cleaner with air ducts.
6. Connect a negative wire to the battery.


EGR temperature sensor (only Californian models)

Removal

 PERFORMANCE ORDER

1. Disconnect a negative wire from the battery.

If the stereosystem established on the car is equipped with a security code before disconnecting the battery make sure that you have the correct combination for input of the audio system in action!

2. Disconnect an electrical wiring from the sensor.
3. Turn out the sensor and remove it from the engine.


Installation

 PERFORMANCE ORDER

1. Screw the sensor on the regular place and tighten it with the required effort (12 H • м).
2. Connect an electrical wiring to the sensor.
3. Connect a negative wire to the battery.


Thermal vacuum valve (TVV)

Removal

 PERFORMANCE ORDER

1. Disconnect a negative wire from the battery.

If the stereosystem established on the car is equipped with a security code before disconnecting the battery make sure that you have the correct combination for input of the audio system in action!

3. Disconnect the vacuum line from TVV.
4. By means of a wrench (try not to touch with a key to fragile nonmetallic parts of assembly) turn out the valve and remove it from the engine.
5. Check valvate assembly for existence of cracks and other mechanical damages. In case of need make replacement.


Installation

 PERFORMANCE ORDER

1. Grease a carving part of the valve with sealant, then screw assembly on the regular place.
2. Tighten TVV with the required effort (20 ÷ 40 H • l), - try not to touch with a key to fragile nonmetallic parts of assembly.
3. Connect a vacuum hose to TVV.
4. Connect a negative wire to the battery.


Electromagnetic EGR valve

Removal

 PERFORMANCE ORDER

1. Disconnect a negative wire from the battery.

If the stereosystem established on the car is equipped with a security code before disconnecting the battery make sure that you have the correct combination for input of the audio system in action!


2. Mark and disconnect vacuum hoses from the valve.

3. Disconnect an electrical wiring from the valve.

4. Remove the electromagnetic valve from a basic arm. In case of need make replacement.


Installation

 PERFORMANCE ORDER

1. Fix the valve on a basic arm.
2. Connect an electrical wiring.
3. Connect vacuum hoses (you monitor marking).
4. Connect a negative wire to the battery.