02 Explorer 4.0 popped a P0402 EGR Valve excessive flow- usually indicating DPFE needs replacement.

I hooked up my AutoTap to try to confirm and got the following readings which don't necessarily mean DPFE, it might be EGR solenoid.

Here are AutoTap readings
EGR DPFE sensor input at time of misfire (there is no code present for misfire)= .4V
EGR duty cycle 0% at idle like it should be, no change with load on engine, my understanding is that it should go from 40-80% to apply enough vacuum to open EGR valve- engine was warmed up
EGR sensor voltage=4.8V which is way out of parameters, should be less than 1V
EGR in failure mode- NO

When I took vacuum line off EGR there was no change in engine performance.

Can anyone help me out?

Thanks

Dave

 

This morning I took off the EGR (for 2 bolts and one nut it took forever) and sprayed some carb cleaner into body under the diaphram. Dried it out with air and the sprayed some in the inlet exhaust gas inlet and it did not bleed by the valve inside, indicating to me that I had a tight seal in the EGR. Replaced EGR with new gasket and went for test drive. SES light did not go out so I came home and cleared it with my scan tool. Will drive around for few days and see if it comes back on.

If it does I think I must assume DPFE needs replaced

 

If you can monitor live data the DPFE should normally be about .9V at idle.
Usually when the DPFE fails the voltage will read either approximately .2 -.4V or above 4V at idle.

 

SES came back on today so I will get the DPFE this week

 

can you tell me where you purchased you DPFE sensor from?please. i just can't seem to find it. My 96 ford explorer was shooting p0401,p0402 and p0420. The mechanic replaced the egr valve and the o2 sensors but the check engine light keeps coming on. I got a feeling the DPFE sensor is really my problem.

 

I just bought one at autozone for 35. It was called egr pressure sensor. Dont say differential or most techs will get off track. I changed mine and it's been 3 days without coming back (still have my fingers crossed).

 

$35 at AutoZone for new DPFE seemed to fix hte problem. They are also available at Car Quest adn NAPA for about $45

 

That’s exactly what happened. Every seemed confused when I asked for a DPFE sensor. Thanks guys.

 

What is the difference between egr pressure valve sensor and egr position sensor?

 

the egr POSTITION sensor is actually a linear sensor that tells the computer how far in and out the egr valve is.