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Exhaust gas recirculation (EGR)

In case of damage or disconnection of the electromagnet EGR valve control electrical signal loss occurs and the EGR valve is locked in the open position at all times during engine warm-up and operation. The symptoms of this situation are the decrease in the efficiency of the engine, infringement of stability of turns of idling and the emergence of the problems associated with the operation of the vehicle.

general description

EGR system is only applicable to engines in volume of 5.2 liters. Its object is to reduce the emission of nitrogen oxides (NO _x) by returning part of exhaust gas through the EGR valve and the intake manifold into the combustion chambers.

EGR valve and electronic transmitter EGR (EET) on engines of 5.2 liters.

Exhaust gas recirculation valve consists of EGR, the transmitter counter to the electromagnetic control valve EGR (EET), the electronic control module (PCM) and the various sensors. PCM is programmed to the optimum value of opening of the EGR valve under all operating conditions of the engine. Sensor EGR valve opening degree determines the EGR valve lift and sends appropriate signals to the PCM. PCM compares the received information with the data on the optimum valve opening, which are determined by analyzing the signals received from the other sensors. If between these values there is a discrepancy, the PCM commands the operation of the solenoid valve control to reduce the depth of negative pressure applied to the valve EGR.

Check

PERFORMANCE ORDER

Start the engine and warm it up to normal operating temperature. Check all hoses and tubes EGR system for signs of leaks, cracks, kinks and traces of material aging. Before proceeding to check the EGR valve must be unambiguously verify the satisfactory condition of hoses. Check the lining of vacuum hoses of EGR (Section General information). If necessary, make adjustments. Disconnect the vacuum hose from EGR valve and instead connect a hand vacuum pump. Create a vacuum directly to the EGR valve and check that the valve diaphragm moves up and down freely, with no signs of biting - at applying vacuum engine should stall. Start the engine and create a negative pressure on the valve depth of 127 mm Hg. Art. The idle speed thus should fall significantly until the motor stops, indicating that serviceability of functioning of system EGR. If the change in engine speed is not observed, it may indicate failure of the EGR valve, a violation patency EGR pipe or channel in the intake manifold or exhaust manifold (this may be caused by the accumulation of carbon deposits). Create a vacuum to the EGR valve and watch the progress of his rod. If the valve opens and closes normally, but the engine does not stall, check channels. Connect the vacuum gauge to a vacuum line electronic transmitter EGR (EET), start the engine and make sure that the valve EET a vacuum required depth. Measure the depth of the vacuum valve EET with the engine running. Also make available to the EET battery voltage when the ignition (key in position ON, the engine is not running). Ignition (and not running the engine) on the valve EET should take place the battery voltage. Remove the EGR pipe and check for violations of cross-ports in the pipeline or reservoir, to see if the tube and have there been any other faults. If necessary, replace the tube EGR. If the EGR valve is heavily clogged with carbon deposits, do not try to scrape them - replace the valve. Remove the EGR pipe and check for violation of patency and damage.

Component Replacement

EGR valve

PERFORMANCE ORDER

Disconnect the electrical connector solenoid valve EGR (EET). Give two fixing nuts and remove the valve EGR. The valve is removed en bloc with the EET. Take two bolts (arrow) at the base EGR valve. Sand mating surfaces of the EGR valve and nozzle. Install the valve EGR, replacing it with a lining. Firmly tighten the fasteners. Connect the electrical connector.

Solenoid Control EET