Pontiac 19210661 Valve Kit,EGR

One of the major emissions control strategies is the Exhaust Gas Recirculation (EGR) system which is to reduce NOX emissions through reduced combustion temperatures through the EGR valve recirculates exhaust gas to combustion chamber. The EGR valve depends on either ported or full manifold vacuum and opens during warm engine operation and engine idle speed and above, and with changes in vacuum and back-pressure on the exhaust determines the amount of recirculating gas. There are three types of EGR valves: positive backpressure, negative backpressure, ported vacuum-all are different and regulated in various ways. The positive backpressure valve includes a vacuum Bleed and the negative backpressure valve varies exhaust gas flow depending on the manifold vacuum and the backpressure of the exhaust system. This valve is ported directly to the throttle so that its operation of recirculation depends on the opening of the throttle. In the case of ECM controlled valves, there is a diaphragm which provides the means by which the exhaust gases are drawn into the intake manifold, while there is a vacuum solenoid that uses pulse width modulations to control the of the recirculation of gases. Every EGR valve is assigned a serial number which is imprinted on the valve body to show what type of valve it is. Regarding non-ECM-controlled valves check for looseness, pressure, and vacuum signals, and check movement of the diaphragm. In the tests done for ECM-controlled valves, solenoid vacuum harness is disconnected and movement of the valve is witnessed under different circumstances. Some of the components require the disconnection of the hoses, the removal of the valve and there has to be adequate cleaning of the valve and passages to avoid the buildup of deposits that hampers the working of the component. Lastly the new components the torque specification and the connectivity between components have to be strictly followed.

Careful handling of vacuum lines and proper sealing are required to ensure functionality during the removal and installation of the EGR valve and thermal vacuum switch.

The EGR system is designed to reduce nitrogen oxide (NOX) emissions by recirculating a small amount of exhaust gas into the combustion cycle to lower peak combustion temperatures, where NOX is formed.

To check the EGR valve, one should inspect vacuum hoses for damage and ensure the proper operation of the EGR solenoid, which is activated under specific engine conditions.

When replacing hoses, the VECI (Vehicle Emission Control Information) label serves as a routing guide. For solenoid and switch replacements, similar precautions regarding battery disconnection and careful handling are advised.

The most common cause is a stuck or corroded EGR valve.

To check the EGR valve, locate it on the intake manifold, ensure the diaphragm moves freely, and test engine response when manually depressing the diaphragm. Additionally, verify that vacuum reaches the EGR valve and check the thermal vacuum switch's functionality with a vacuum gauge.

The EGR valve is opened by manifold vacuum.

With the engine cold, you can reach under the EGR valve and manually push on the diaphragm. Using moderate pressure, you should be able to press the diaphragm up and down within the housing.

Yes, proper procedures for installation are outlined for replacing the EGR valve or thermal vacuum switch.

If the EGR valve fails either of the tests mentioned above, it must be replaced.

The EGA valve is located on the intake manifold, adjacent to the carburetor.