had the same problem. two possible causes. first take off the egr valve and spray carb cleaner down the flow port. (dont do like i did and use the wrong carb cleaner it must be the type that says safe for catylic converters or you will burn them up) like i said spray carb cleaner in the port until it unstops put the egr valve back on and take it for a 10 mile spin accelerating to blow trash out of the catylic converter. if this does not work well you are in for a real surprise. the 3.0 has 3 catylic converters each costing over 450.00 apiece for the 2 on the motor and over 600.00 fot the big one on the bottom. also about 800.00 labor. if the emmisions test shows low recirculation and number 1 plug you can bank on the bottom converter being bad. for the two on the motor it depends on which plug is missfiring on the diagnostics code to which bank needs to be changed. also there is an egr pressure sensor behind the motor and ithas 2 vacum hoses attached no one at the part store will know what it is but you might need to change that too its only 35.00 that monitors the back pressure from the exhaust port to the catylic convertor it can stop up with suit from the exhaust. even though i had to do all this every year my wife and i have to wait until the light goes out to get the inspection to pass. the emmisions test says we have a bad catylic convertor every time even though we changed them and the light comes and goes . good luck
Trouble code PO402 is a generic (all car makes) code meaning "Exhaust Gas Recirculation- Excessive Detected". It means that the computer detected an abnormal or unexpectedly high rate of air flow in the exhaust gas recirculation emissions system.
exhaust recirculation valve, helps with your emissions
exhaust gas recirculation flow insuffcent detected
exhaust gas recirculation flow insufficient detected
P0400....Exhaust Gas Recirculation Flow P0401....Exhaust Gas Recirculation Flow Insufficient Detected I can't find any that has a .1
The unburnt exhaust gases are recirculated back through the engine by way of the intake manifold. This helps reduce emissions.
Exhaust gas recirculation insufficient flow detected
Trouble code P0401 means: Exhaust gas recirculation - insufficient flow detected
Trouble code P0401 means: Exhaust Gas Recirculation Flow Insufficient Detected
po401 mean Exhaust Gas Recirculation Flow Insufficient Detected.
P0401 Exhaust Gas Recirculation Flow Insufficient Detected
Trouble code P0401 means: Exhaust Gas Recirculation Flow Insufficient Detected