My wife drives a 2002 exploder and we keep getting the check engine light. These are the codes we have been getting:
P1000 Monitor checks not complete. More Driving required
P1400 Diff Pres Feedback EGR Circuit Low
P0443 Evap Emission Ctrl Sys Purge Ctrl Valve Circ Error

After testing the EGR valve with a vacuum pump, it seems fine. Then we tested what I thought was the Differential pressure Sensor for the EGR for resistance and got readings of 31ohms one way and switching the leads got 20ohms. On the plugin that comes from the computer we also verified it does have the same amount of volts that the battery does.

I feel that this Differential pressure Sensor is what the problem is, but I went to the dealer and they couldn't get me the part without a part number. This piece looks like a cylinder about 1" in diameter and has a mounting bracket. On the side it has two 3/8"+/- vacuum lines coming in and then one smaller one off the bottom that goes to the EGR valve. It also has one two prong plugin that goes back to the computer I assume, which was measured for voltage.

Anyone know the part I am looking for and if you think it's a likely culprit given my DTC codes? What else might it be? Thanks for your help!

J.D.

 

I think you have mistaken the Electronic Vacuum Regulator (EVR) for the Differential Pressure Feedback Sensor. The EVR is a round plastic part on the side of the intake manifold and has a vacuum line coming from the intake manifold and out to the EGR. The DPFS is a rectangular, flat box with two vacuum lines dropping down towards the exhaust manifold and is mounted on the side of the driver's side valve cover (at least for the V6 SHOC). Don't assume the sensor is bad; check to make sure the lines from the exhaust manifold to the DPFS are in good working order. Broken or plugged lines can damage the sensor.

The DPFS sends codes to the computer and the computer controls the EVR to send vacuum to the EGR with pulse width codes.

Also connected to same vacuum lines is the Evap system for the gas. The valve control is under the battery. If it has problems, it could be removing the vacuum on the EGR control lines, causing EGR problems. If you put a vacuum on this line, it will hold at about 1 PSI.

I have found loose vacuum lines on my Explorer so make sure they are good first.

You should be able to get a part number for the DPFS on a parts website like www.rockauto.com. The EVR is available at the dealer and they should be able to find it your VIN.

 

Meanwhile I was doing some of my own research and I think you are right, the part I assume is bad is the EVR. But based on my codes, where would you start? It's the 4.6L V-8 and the EVR is just in front of the brake booster. Thanks for your help.

J.D.

 

The DPFE sensor is a common culprit on past models. But based on the "P0443 Evap Emission Ctrl Sys Purge Ctrl Valve Circ", I would look at it first. In fact, It might be as simple as a missing or damaged vacuum line. Check out the function of the Evap control valve and all the parts associated with it, or the electrical connection to it. I do not know how to check it. Perhaps someone else can give you some help there.

I would think that by plugging the vacuum line to Evap Ctrl Valve, the EGR system should then work properly, if the Evap system is the problem. You could check to see if that gets rid of your EGR problem and then work on the Evap system. However, I wouldn't operate the car normally without the evap connected or other problems might arise such as a build up of gas fumes in the system and poor emissions control. But it might work as a troubleshooting tool to see if the EGR system is in fact working.

 

Usually when we cleared the codes, we'd get them back the very next time we drove. After all the testing we did, the codes aren't coming back. Does the EGR stick sometimes? Is it possible that we fixed the problem just by actuating the valve with a vacuum pump? That would be if we did, but somehow I think eventually they'll come back. But until then, it ain't broke!

Thanks for your help!

 

My first post, but I think I might be able to help:


My 2002 Exploder set a code recently as well (I think it was a 1400)... anyhow, it matched a code I remember seeing in the TSB section on the alldatadiy.com website... in my case, it was a 45.00 sensor (I think DPFE)... I swapped it, reset the codes, and the problem's gone.

BTW, I did get a notice from Ford about a month after the problem happened, announcing that they were extending the warranty on that one part to 40,000 miles... fat lot of good that would've done me, I'm almost @ 60,000 miles now... and I've already had to put a transmission in it! What's with Ford and trannys, anyway?

 

I will keep that in mind, but still no codes!

Thanks!

 

I think we should all line up our 02 explorers and start a convoy to get attention.. That way we can waste gas, time off work and still get nowhere

 

BTW, the TSB I mentioned I think also said that it was an intermittent issue.. so I'm sure the codes will be back again someday, if it's the same problem.

 

Got the codes back, so i replaced the DPFE sensor and so far so good. I think I replaced it a week ago this Wed. Thanks for your help. I am sure you'll hear from me if I get the codes back!!

Jman

 

No problem. It's apparently one of those common problems, like the bad RABS sensors on Rangers!