Test Description
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2002 Pontiac Grand Prix, 2002 Pontiac Bonneville, 2002 Chevrolet Monte Carlo, 2002 Chevrolet Impala, and 2002 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step numbers in the diagnostic procedures.
- 2
This step verifies that the malfunction is present. - 3
If DTC P0404 will only set under certain conditions, the malfunction may be intermittent. See DIAGNOSTIC AIDS . If an intermittent wiring problem is not present, test for a faulty connection at the PCM or the EGR valve. If the connections are okay and DTC P0404 continues to set, replace the EGR valve.