So, I searched this...the DPFE sensor is what I want to replace? Not the EGR valve? ($62.93 for the valve at the stealership...not bad) Didn't price the sensor..prolly $200+. Should I replace the EGR valve anyway (doing it myself)?

Thoughts?

 

It can't hurt to replace both.

 

DPFE msrp is ~ $66 at the dealership.

Should you replace the DPFE and not the EGR? Google on "duratec dpfe p0402". This is a very common issue with Fords. Now for the disclaimer - 99.9% of the people posting are not certified Ford mechanics nor have they seen your vehicle. The DPFE is most likely your issue based on a high percentage of others having the same issue. Now you could take your vehicle to the dealership but they could also just replace the EGR, DPFE and possibly other parts at a very high cost.

 

I'll just start with the sensor I guess and have the code cleared...if it comes back, then I'll do the valve. I only need this truck for 1 more winter and hate to throw a bunch of $$ into it by paying for the dealership to do work I'm perfectly capable of doing myself. I'm playing by the law of percentages here, if it's the MOST likely culprit, then I'll replace it first.

 

You can clear the code by disconnecting the battery for 15 minutes or so. If the issue still exists, I believe the light comes back on after you've started the engine and driven it 3 times.

 

It is usually a waste of money to replace the EGR valve. They very seldom fail.

It's your money....

The CEL comes on if a fault is observed by the PCM on two consecutive drive cycles in the which the relevent test has been run unless it is a "hard" fault.


Steve

 

The DPFE sensor has three wires.

One wire should be 5 volts. This powers up the sensor.

One sensor is zero volts. This is the sensor ground.

One wire is 1 volt. This wire is the signal return wire. The signal return wire must be 1 volt with the ignition key on and the engine off. A bad sensor usually shows 0.5v (1/2 volt) or less or 3 volts or more when it fails.

The above voltages are checked with the sensor electrical connector plugged in and the wires are back probed with the Red lead of a digital volt meter. The Black lead of the voltmeter will be connected to ground or the negative battery terminal and not be moved during the above checks.

If I knew what model year and engine size you have I can give you the wire colors of the sensor and which wire has what voltage.

 

great info...thanks..it's a 2001 XLT with the 3.0 ltr engine. I have a meter so i can check the volts. Going away for the long weekend so I cant do it right away, maybe next weekend!

Thanks for all the info...saves me a bunch of $$!!

Kevin

 

Pejeeper:

Brown/White wire is the 5 volt wire

Brown/Light Green wire is the ground wire

Orange wire is the signal return wire which should be 1 volt key on engine off

 

update..light went off yesterday...for quite a while on a small road trip...came back on today...gotta be the sensor, will change it out when I get back next weekend. Thanks for all your help!

 

The engine isn't running rough at idle is it?? That will cause an excessive flow code to set (P0402).

If it was my vehicle I would check the sensor voltage first. Once the voltage at the sensor is found to be incorrect, indicating the sensor is out of range and needing replacement, I would be confident that the sensor would indeed solve the problem.

 

Sensor voltage was off on the orange wire, reading .2 to .3 volts. Replaced the sensor and resetting the computer..waiting to re-hook the battery wire until I leave for work tomorrow. Sensor cost about $50 at NAPA.

 

Engine light went off on it's own after about 20 mins of driving. Re-tested the voltage after light went off, all tested normal...thanks for the help....

 

You are welcome

 

I have a 2002 Escape (is hers, actually) with a 3.0L Duratec. It started reporting both P0401 and P0402 a week ago. It's otherwise running fine. I'm about 99% sure it's a DPFE problem.

I don't think I can count how many EGR valves I bypassed in the old days (it is legal to do so in my state). Just plug the vacuum line, or remove the entire valve and bolt on a block-off plate, and off you go with better overall performance.

I'm inclined to plug the EGR vacuum control line on the Escape, to keep the EGR valve in the closed position, but having the CEL lit all the time would give my old lady ulcers. It would also be nice to have the light still functioning to handle the case of a failure of the oxygen sensor or some other emissions control.

So, disabling the EGR is cake, but how to stop the P0401 and P0402 errors without disabling the Emissions Control dashlight entirely?

Would maintaining 1V on the "return sensor wire" when the ignition is on keep the light off? Regardless of whether the engine is off, or running at any RPM?

Maybe a resistor (what value?) from the 5V lead to the sensor wire would do the trick, or maybe a small DC voltage regulator like the 3-connector LM317? Soldering 5 diodes in series would yeild a 3.5V drop leaving 1.5V to the sensor wire... Any ideas? I'm concerned the voltage on the sensor wire varies under different operating conditions, but am not sure how particular the ECU is before triggering the fault and the error codes.

If I could trash the worthless EGR and have the light working otherwise for a couple bucks, I'm game. Otherwise I guess it's $66 to Ford for a part which likely costs them $3.

Thanks.