Ford Ranger 2000 - P0401

[stup1d]

Hello,
I have a 2000 Ford Ranger V6 3.0 Flex Fuel ~ 46k miles (bought it used at 30k miles in 2003). Two days ago the check engine light came on while driving in the city. I'll try to be as detailed as possible, sorry if its missing some info.

I search around the internet (found this forum) and found that there is a common problem with the EGR valve and/or the DPFE sensor on this particular year Ranger.

I disconnected the battery to reset the sensor. When I reconnect it, the check engine light is gone and after driving it around town for a while it did not reappear.

The next day I drove it about 16 miles one way in the highway to a state park going 60-70 mph, still no light. On the way back the check engine light came back on. Took it to autozone and it gives P0401, the guy suggested to replace the EGR valve for $53 but since it might not be the culprit I didn't purchase the parts.

Called a friend that works on trucks and he also suggested to replace the valve but he said since the light doesn't immediately come on I could probably just clean the valve (unfortunately he is unavailable to come and help me anytime soon). I tried to clean the valve but I have problem getting it off the EGR tube after releasing the 2 bolts.

There's no problem with engine performance, no pinging, no problem in starting, etc. I notice there is a loss in efficiency for city driving with the AC on its using up more gas. Whenever I disconnect the battery, the check engine light will disappear and reappear after prolonged driving.

After reading some more about it, I'm getting more convinced that the DPFE sensor is the one not working. The one I have is an aluminium one. A new DPFE sensor (plastic) cost pretty much the same with a new EGR valve.

I would appreciate any inputs and/or suggestion regarding my situation ?
Is there a way to pinpoint whether its the EGR valve or the DPFE sensor that's malfunctioning ?
Is it true that the only negative effect from this is the poor gas mileage or could it cause bigger problem(s) that could be bad or even dangerous ?
I need to take a family member to an airport (about 60 miles away) in a few days so I'm wondering if I can still drive it as it is or have it repaired first.

Sorry if this has been asked and posted so many times in the forum and thanks in advance.

[squeaky3]

there is a good chance that it is the stock DPFE that is malfunctioning
we do alot of them at my dealership
take it to a local dealership and tell them about it
im not sure exactly how much it wil cost becuz the part is diff for each car but ya take it in and have them look at it

[carlos80]

you can test the valve for flow without having to remove it. Just use a hand vacumm pump or attach a hose that fits snug onto the port on top of the valve. Using either the pump or just sucking on the hose with the truck idleing should cause it to stumble, if enough vacumm it applied it should stall out. This test will indicate if your system is capable of flowing exhaust gases.
The valve should hold vacumm too if it doesn't then you could have a torn diaphragm, in which case you would have to replace the valve.
No engine stumble but does hold vaccumm means the EGR passages are probably clogged up.
If it all checks out then I would really recommend replacing the DPFE

[nymorey]

Originally Posted by squeaky3

there is a good chance that it is the stock DPFE that is malfunctioning
we do alot of them at my dealership
take it to a local dealership and tell them about it
im not sure exactly how much it wil cost becuz the part is diff for each car but ya take it in and have them look at it

I ended up replacing the EGR valve, then the solenoid..........afterward I found this forum and FINALLY replaced the DPFE sensor. An expensive fix for me

The factory DP sensor is made of metal and corrodes. The new ones are plastic.

My vote is to check the DPFE sensor

[Bradley Brake]

EGR good.Replaced solenoid-DPFE-checked vacuum lines.O.K. Reset code with scan tool.After 30 miles of driving light comes back on.Engine is rough when light is OFF but smoothes out when light comes ON.Vacuum lines seem good. Need help.

[juan wassen]

I can describe the exact same problem (as stup) on my 96 ranger (2.4 l). its been like that for over a year now, it still gets 24 miles/gal. I now have to correct it in order to get it to pass state inspection.

I will start with the vacuum lines because i've noticed the vent actuator malfunctioning depending on how much the throttle is open when driving down the highway, and the a/c will suddenly be blowing only to my feet.

I'll keep you posted on what I end up correcting.

[tripod12133]

To test the DPFE sensor:

Turn your key all the way forward but do not start your truck

Get a volt-meter. Stick your positive end into the line on either side on the connector (but not the middle wire - there should be 3 wires altogether)

Get a piece of vacuum tubing. Hook it took the DPSE sensor.

Blow through the line, and watch your volt-meter

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If you see a reading of up to 5 volts, your DPFE sensor is good. Youll notice that as you blow harder, it registers more volts.

If you dont see a reading, or it is not increasing in voltage, then it is the DPFE sensor.

I did this on my 95 Ranger 2wd 2.3L to troubleshoot the egr system.

I hope this helps.