EGR system

The EGR system returns a small amount of exhaust gas into the intake manifold. This reduces the overall combustion temperature. Cooler combustion temperatures provide a significant reduction of the Nitrogen Oxides (NOX) in the exhaust emissions.

The EGR valve:

• is electronically controlled by the PCM.
• is connected to the exhaust manifold by the EGR valve-to-exhaust manifold tube.
• controls recirculated exhaust gas flow to the intake manifold.
• monitors the flow of recirculated exhaust gases through the EGR valve-to-exhaust manifold tube.
• returns a signal to the PCM.

The amount of recirculated exhaust gas depends upon:

• engine rpm.
• intake manifold vacuum.
• exhaust back pressure.
• engine coolant temperature.
• Throttle Position (TP).