Exhaust gas recirculation (EGR) - the general information, check of a condition and replacement of components

1. On models prior to 1998 MY. of the EGR system includes EGR valve, a solenoid valve (EGRS) associated with the suction port and a conduit, a temperature sensor, and EGR valve backpressure sensor (ART). PCM controls the operation of the system through a solenoid valve EGRS. In the intake air path is a special valve located directly behind the throttle valve. The vacuum inlet port is monitored through a valve located throttle body. When the acceleration throttle is opened, resulting in increased depth of the vacuum in the intake manifold.
2. Valve switch ART monitors exhaust backpressure depth when changing the engine speed. Information from the temperature sensor EGR, use RSM to manage the flow of exhaust gas recirculation by turning on / off system.

1. Check all hoses for cracks, twists and other mechanical damage. Rate compression fittings for leaks.

2. To check the serviceability of functioning of system EGR warm up the engine to normal operating temperature. Put the transmission in neutral position, cock a lay brake and prop chock rear wheels. Leave the engine running at idle. Opening the throttle raise the engine speed to 2000 ÷ 4000 rev / min, and then re-close the damper, - the EGR valve stem to move when changing speeds. Repeat the test several times. If the stock does not move. Check the supply of the vacuum signal to the valve EGR. Disconnect the hose from the valve and pressing his finger slice, repeat the procedure. If there is no vacuum in the hose, make sure the tightness corresponding compression fittings, and then proceed to check the solenoid valve EGRS.

1. With the engine off and disconnect the vacuum hose with a hand vacuum pump to create a vacuum on the EGR valve depth of about 25.4 mm. Hg. Art. If the valve is opened, measure its stroke, which should be about 3 mm. Replace the faulty valve.
2. Re-create the vacuum and press a hose. The valve must remain open for at least 30 seconds, otherwise a violation of integrity and diaphragm assembly should be replaced.
3. Start the engine and create a negative pressure on the valve. When the valve is open must be a violation of the stability of the idle speed, otherwise it should be ascertained in the absence of violations of cross channel in the inlet pipeline. If no changes in the engine speed when opening-closing valve occurs may last generally stuck in any of the positions. Remove the EGR valve and check the plate and its seat for foreign deposits.
4. If a strong carbon formation valve should be wiped with a solvent, making sure it does not come into contact with the diaphragm.
5. Use the hand vacuum pump lock valve in the open position, and carefully scrape off the softened layer of fat solvent from the working surface of a plate and its seat. Estimate degree of deterioration of working components, if necessary, replace the valve assembly.

1. Check the feed to the vacuum valve with the engine running. If there is no vacuum, check the corresponding vacuum hose and compression fittings. If the hoses in the order, check the patency of the union on the throttle. If a vacuum is applied properly, disconnect the valve EGRS wiring and check if the feed to the contact terminals of the connector the battery voltage with the ignition on (do not start the engine).

2. To check the serviceability of functioning of the electromagnetic valve EGRS disconnect the wiring and grounding one terminal, with a jumper wire, connect the second to the positive terminal of the battery.
3. When the power supply must be free to air blown through two fitting located next to each other. When power is turned off valve must overlap.

1. Disconnect the air intake hose from the throttle body and the air cleaner assembly (see chap. The power supply system and release).

2. Disconnect the vacuum line from valve EGR. Give a nut couplings.

3. Release retaining clips.
4. Remove the EGR valve from the intake manifold. The old seal can not be reused and must be replaced by the installation mandatory.
5. Wire nozzle Clean mating surface of the valve inlet pipe. If the valve is replaced, strip and its mating surface. Use a screwdriver to scrape coal deposits.

To prevent damage to the diaphragm, in any case not flush valve in solvents! Not recommended also resort to sandblasted mating surface.

6. Excessive carbon formation EGR channels can be cleaned with a wire brush. In order to avoid violations of cross valve, make sure that all the grit has been carefully removed.
7. If heavily soiled, remove valve EGR pipe from the exhaust manifold and clean it from the inside. Note: Remove the valve switch ART and carefully remove the grit from all channels.
8. Install in the reverse order.

1. Disconnect from the control solenoid valve EGR (EGRS) wiring.
2. Carefully Mark and disconnect all vacuum tubes.
3. Give a fixing nut and remove the solenoid valve.
4. Install in the reverse order.

1. Disconnect the wiring from the sensor and remove the last of the tube.
2. Before installation, lubricate the threads on the sensor antiprihvatyvayuschim sealant.
3. Install in the reverse order.

On models 199 MY. EGR system consists of valve EGR, arranged on the principle of a stepper motor, a temperature sensor, and EGR control module (PCM). PCM controls the flow of exhaust gas recirculation, by opening and closing the EGR valve in small steps. The system allows for fine dosing flow EGR, achieving the maximum return from the engine.

1. Check the power supply to the valve EGR. Disconnect the electrical wiring and switch on the ignition. Ground the negative lead of the voltmeter to ground, connect the positive turn to the terminals of the two red wires connector. In both cases, the meter must register the battery voltage, or check the status of the wiring on the circuit between the battery and the relay ECCS (not forgetting the fuses) and the relay valve and EGR (see. Wiring diagram at the end of the Head the Onboard electric equipment).

2. Use an ohmmeter to measure the resistance between the connector terminals valve EGR. At room temperature (20 ?� C), the result of measurement should make 22 ohms, otherwise replace the valve. If the valve is okay, the car should be driven away on a car repair shop for diagnostics proedeniya PCM and perform necessary regenerative repair.

Remove the temperature sensor EGR. Lower the probe tip in a container of water. Begin to heat water, tracking the change in resistance of the sensor. With increasing temperature, the resistance must fall, and at 100 ?� C to reach a value of 10 ÷ 30 Ohm.

1. Disconnect the air intake hose from the throttle body and the air cleaner assembly (see chap. The power supply system and release).
2. Move aside the hoses and wiring to ensure access to the valve EGR.
3. Disconnect the EGR.
4. Release fixing clips.
5. Remove the EGR valve from the intake manifold. The old seal can not be reused and must be replaced by the installation mandatory.
6. Use the scraper carefully smooth out interfaced surfaces of the valve and piping.
7. Install in the reverse order.

1. Disconnect the wiring from the sensor and remove the last of the pipeline.
2. Before installation, lubricate the threads on the sensor antiprihvatyvayuschim sealant.
3. Install in the reverse order.