Contour Enthusiasts Group Archives Forums General Troubleshooting EGR / DPFE (Code P0402)

Okay,

I did a search and found all kinds of stuff on this code and the DPFE and EGR. I through the P0402 about a year ago and fought and finally replaced the EGR valve (what a bear!) I just put new Autolites in and the car was running great. All of a sudden today I stomp on it to get out of the way of some joker and it starts bucking a bit. Then when I come to a light its running rough with the console sort of dimming a bit when in a really low idle.

I am tinker with it in the garage when it throws a Cell. Get my trusty OBDII reader and fine the P0402. I still get these every now and again even after the new EGR.

I do have a bit of a hissing sound from the left front (serpentine belt) side of the engine.

Now, could I have a bad DPFE, vacuum hose, or someting worse? So far this year I have had a new Tranny and A/C system put in the beast, so the thought of dropping more into it is just killing me (already down $3k+, but it's paid for!)

Any thoughts?

could be the DPFE sensor, try applying vacumm to the egr and see if the car stalls, if it does the EGR valve is good and the DPFE is bad

I suggest you replace the EVR.

The EVR should never open at idle, no matter what the DPFE says.

On that note you may want to check the TPS operation.

EGR Vacuum Regulator - Opens the EGR valve.


Throttle Position Sensor - From idle to WOT (wide open throttle).