Exhaust Gas Recirculation: Description and Operation

P0400 EGR Function (close)







This system cuts and controls vacuum applied to the EGR valve to suit engine operating conditions. This cut-and-control operation is accomplished through the ECM and the EGRC-solenoid valve. When the ECM detects any of the following conditions, current does not flow through the solenoid valve. This causes the port vacuum to be discharged into the atmosphere. The EGR valve remain closed.

P0402 EGRC-BPT Valve Function




The EGRC-BPT valve monitors exhaust pressure to activate the diaphragm, controlling throttle body vacuum applied to the EGR valve. In other words, recirculated exhaust gas is controlled in response to positioning of the EGR valve or to engine operation.