EGR Code P0402 on Ford Escape 3.0L

Factual Questions
1

Last year in November my wife’s car showed code P0402 EGR Excessive Flow and we took it in to have a part replaced. The code has come back this year, and I am going to make an appointment to get it checked out again, but I woudl like some opinions as to what might have caused the recurrence.

The mechanic at the garage did not tell me what he thought it might be. I am wondering if overfilling the oil could have caused this. The dipshits at the oil change place (see my thread on replacing the oil drain plug for a second time) definitely overfilled the oil, because in changing the plug I know I let out at least half a quart, plus the drips that had leaked out, yet the dipstick still reads at or above the “full” mark when I look at it. Could this be a possible cause? Are there other possible common causes I should be aware of?

2

I’m not aware of excess oil causing that code. Among the more common possibilities are a faulty vacuum switching valve, vacuum hose problems, a faulty DPFE sensor, and poor connection in the ground circuit to the sensor. Experience has shown that some aftermarket DPFE sensors have problems; if that’s the part that was replaced it might have failed. Otherwise, there’s likely a different cause this time.

3

That was it, the DPFE sensor was replaced. They are going to examine it to see if it has failed again. Hopefully it will be under some sort of warranty if it is.

Thanks Gary!

4

So yesterday we got in and the light wasn’t on anymore. Wierd.