jbrew -

Wonderful pics and threads to look at! Thanks so much. I talked to a friend of mine and we did a little diagnosis over the phone. Here's the results:

- Disconnect vacumn line from EGR and used vacumn pump. No vac, engine ran fine. Draw some vacumn and engine started running rough. Vacumn held as well.

- Hooked up vacumn gauge to the EVR. At idle there was no vacumn. When I revved the engine a little and then held the throttle at a set position, the vacumn gauge would go up to 10'ish then drop back to zero.

Based on the above, the EGR should be ok and the EVR as well. I replaced the DPFE from Autozone about 6 months ago. The friend's suggestion was to remove the EGR tube and replace it. The idea being there is probably alot of carbon build up in it. I have a 99 Expedition with 180K'ish miles. It sounds like I should try to clean the intake manifold as well.

The nuts on the EGR tube look pretty solid and scary to me. Any input on which way to go?

I just changed the CV axels on my Dad's 95 Honda Civic, so I'm not afraid of removing/replacing things. I just need smart folk such as you all to tell me the names of parts and help diagnose. Kinda like tele-surgery for doctors!

Any input is appreciated.

 

Far more likely that the AutoZone sensor has failed. The Ford replacement is highly recommended, even at around $100. You can order them from online Ford parts suppiers for under $50.

Theres not much of a chance there's anything wrong with the EGR tube. Never heard of one with any problem besides getting broken.

Hook your vacuum guage in the sammple lines to the EGR tube. Pull a vacuum on the EGR valve to activate flow. Measure the differential vacuum between the sample ports. Now, repeat with a DC voltmeter attached to the output of the DPFE sensor. You should see a linear change in the sensor output that corresponds to the difference in the vacumm sensed at the DPFE sensor inputs. There's probably a chart around here somewhere, otherwise, someone can probably dig one up.

Steve

 

Oh yeah that's right - Ford updated the DPFE , but I heard you have to go to the dealer to get it...

I'll bet it's the Auto Zone sensor as well.. I'm curiouse what the Ford update consisted of myself, that might explain why the DPFE sensor you purchased might not be functioning properly.

If you don't have a Haynes manual, it's a good idea to grab one of those and/or purchase a vehicle specific account with ALLData.com for how to's, charts, diagrams, TSB's, Part #'s, etc...

 

I checked the sensor paperwork and realized it was still under warranty. I went down to AutoZ and swapped it with a new one. The code didn't clear yet. I'll get it cleared if it doesn't go away during normal driving tommorow. If it shows back up I'll clean the intake. In the meantime I can find out where to get an OEM DPFE.

I'll post back with some success I hope.

Thanks so much for the input!

DrA>

 

Is the replacement sensor metal or plastic? What is its rand and part number?

What year and engine are you working on?

As for resetting the CEL, you have several options:

1) Drop back by AZ and ask them to reset it with their scan tool.

2) Identify the PCM fuse (usually 5A or so) from your owner's manual. Remove it and wait 10-15 minutes. Replace it and drive the truck to tlet the computer re-learn operating paramters.

3) Disconnect the negative battery cable, then follow the rest of #2. Reprogram your radio and clock.

Steve

 

Heres the old part # and cost I believe - They should have a cross reference number for the 9J460 updated sensor - it should come up automatically if they enter in this number on there comp. at the dealership or Ford parts supplier in your area. Just make sure the part number differs from the one below if you decide to purchase one - the updated DPFE will have a different number..

That's dealership pricing below lol..

Parts
. OEM Part
. Price
Pressure Feedback Exhaust Sensor
.
. Pressure Feedback Sensor
. F77Z9J460AB
. $103.38
Notes
Labor
. Skill
Level
. Mfg.
Warr.
. Std.
Pressure Feedback Exhaust Sensor
.
. Replace
. B
. 0.1
. 0.3
Notes
.
. Does Not Include: EEC Quick Test Or Pin Point Test Diagnosis Time.

 

The code has cleared itself since I replaced the DPFE. I'll monitor things and probably go ahead and get the OEM metal one in a few months, based on the info here.

Should I go ahead and remove the intake and clean it just as preventative maint?

Regards,
DrA>

 

That's always a good idea if it hasn't been done in awhile, those automotive pipe cleaners work well in the ports..