'97 Escort EGR Problems, Error Codes P0401, P0402

My MIL check engine light came on and has stayed on for quite a while now. I finally decided to look into it.

I've been getting both error codes P0401 (insufficient flow detected) and P0402 (excessive flow detected). I initially thought it was a bad EVR solenoid and changed it out with a brand new one from the dealer and reset the codes. Less than 24 hours later, the two error codes came back on. Then I thought it could be a stuck EGR valve so I got a new one and swapped it with the old one. Same thing happened, the two codes came back on in less than 24 hours.

Has anyone else had the same problem? What else could it be?

Thanks for your help.

I have the same problem, but my mechanic "cancelled" the egr valve and solenoid, and told that this valve doesn't affect the performance of my vehicle. Is this True..??

The problem, it seems, had to do with the DPFE (Differential Pressure Feedback EGR) Sensor. Apparently, Ford is notorious for making defective DPFE sensors. I read on some other forum that if Fords give those error codes, it's most likely the DPFE sensor and so I gave it a shot. I went to Autozone and bought one (it's called EGR Valve Pressure Sensor) for around $55 and installed it in around 15 minutes. The error codes never came back.

So, if you're still having this problem, you might want to give the DPFE sensor a shot.

Hope this helps!

I'll give it a try...Thank you very much.

Hi, Again....are The Egr Valve Possition Sensor And The Egr Valve Pressure Sensor The Same....?????
Thanks

I'm not sure what an EGR Valve position sensor is, sorry.

You should check at http://www.autozone.com for the EGR Valve Pressure Sensor.

What are tools I need to replace the DPFE sensors? I have a 99 ford taurus with the same problem.

I think all I used was a socket wrench. I don't remember which size though. Nothing special.

for the escort was a 5/16". Maybe you'll need two of them.

Thank you so much. The mechanic charges $80 for labor.

I have put on a new EGR valve pressure sensor. But the engine light is still on. Then I disconnected the battery for 3 seconds and connected it. The light is off. Is this right? Do I need to do that. I quite worry about this light come back again.

normally you reset the light with the computer. But I heard that some people disconnect the battery in order tu shut the light off. But I'm not sure if it's the same thing....

Jerry, you should put some miles on the car -- probabliy around 50-100 miles or so. If it doesn't come back on, it should be fixed.

Thanks
Actually, I have put 1k miles last weekend. It still does not come back.

I have a 1998 Ford Escort SE. I had that code also, bought the DPFE (Differential Pressure Feedback EGR) Sensor at AutoZone that the person before mentioned and the code still came back. $55 down the tube. I guess it was good to get out of the way that it was not the sensor. I am going to have to physically check the whole thing out. I guess I was just trying the expensive lazy man's way out. It's just that I read that the sensor was the problem 95% of the time so it was worth the chance. I, ofcourse, reset the computer.

were is the dpfe/egr located at

I have a 1998 Ford Escort SE. I had that code also, bought the DPFE (Differential Pressure Feedback EGR) Sensor at AutoZone that the person before mentioned and the code still came back. $55 down the tube. I guess it was good to get out of the way that it was not the sensor. I am going to have to physically check the whole thing out. I guess I was just trying the expensive lazy man's way out. It's just that I read that the sensor was the problem 95% of the time so it was worth the chance. I, ofcourse, reset the computer.

did you reset the computer after making the repair? if not remember the computer retains the code for a large amount of time/start ups