how to test the sensor(s)

[rocco123]

I was wondering how I can check the DPFE - Delta Pressure Feedback Exhaust sensor & the EVP - Egr valve position sensor on my '94. I did check the egr valve by verifying it opens when I put a vacuum to the nipple.

I recently confirmed the operation of the same sort of EGR control valve on my Interpid by verifying it opens when voltage is applied to the connector & believe the explorer valve (that contols vacuum to the EGR valve)should work the same way. Apply voltage & it should open ... right?? On the Intrepid it turned out to be the EGR valve had a bad diaphragm ( discasembled and found a cut in it).

I'm not the kind of person who shotguns parts unless I have probable cause.

"Check engine light"....Explorer codes are:

335 EGR voltage out of range

539 AC on during test ( oops: )

332 egr valve opening not detected

Again, I do not loose vacuum when applied to the EGR valve & when vacuum applied the valve opens all the way.

Any help appreciated.

 

[DonM]

I dont believe you can test the DPFE, sounds like you got the rest covered?

 

[rocco123]

I'll see if I can find a EVP - Egr valve position sensor at a junkyard & replace that.

 

[MrShorty]

I know there are circuit tests that check operation of the DPFE. See if you can get a hold of a complete EEC-IV diagnostic article (Try repair manuals in the library, or search in the Explorer forum back to last summer at www.ford-trucks.com/forums for a file called "gtest.pdf") That will contain the circuit tests for the trouble codes you are getting, which will include a test of the DPFE.

 

[rocco123]

Thanks shorty. I'll try that when I get back in town.

Rocco