What causes p0402 in a 96' ford contour with a 2.0 engine?
Trouble code P0402 means: Exhaust Gas Recirculation Flow Excessive Detected
A P0402 indicates that the PCM is seeing voltages higher than expected from the DPFE(Delta Pressure Feedback Exaust) sensor. The DPFE is the EGR position sensor. The high than expected reading could be caused by an EGR valve that is either sticking open, EGR valve that is being held open by the EGR vacuum regulator, or it could be a faulty DPFE sensor.