Emann0007

okay, so I have replaced the EGR valve and the sensor and again the check engine light has come on reading EGR valve flow excessive WTF do I do now?

sprostang

It can also be your TPS, MAF sensor, coolant temp sensor, check those out to see if their good. They will fall under EGR failure if messed up and cause CEL to come on. Hope this helps.

Emann0007

I have replaced the TPS also.... it said excessive flow, so that would rule out the MAF right? Cause it did say "Excessive flow EGR"

sprostang

Yeah, that should rule out the MAF. I would try putting in the stock MAF, disconnect the battery for about 10 minutes, then reconnect and see what happens. I assume you also checked your vacuum regulator and checked for leaks, right?

Derf00

What's the specific Code P0171 or P0170 or P0172? If it's any of those three...stop and go get a DPFE (Differential Pressure for EGR) switch. Common problem on ALL Ford F-150, Escapes, and some production date specific Mustangs. The EGR sensor is fine, the DPFE switch controls how much to open or close the EGR valve, not whether or not to turn it on or off.

Those switches get stuck open a lot and that causes the EGR valve to get stuck open. Not because the EGR valve is bad, but because the switch is telling to open all the way.

http://www.motorage.com/motorage/art...l.jsp?id=54993
Look at 2000-2002 Models towards the bottom of the page. Those codes also indicate a problem with the sensor but are not as common as the ones I mentioned above.

Derf00

That will only clear the code temporarily. It will come back until that DPFE switch is replaced. I've had a personal experience with it and so have a couple of people I've known.

sprostang

I know that it is only temporary. But when changing the MAF, as well as other parts, your supposed to disconnect the battery to reset the computer when using a new part. But anyway, I did a little research on this problem because I was curious for my own good and from what I came up with sounds like your right about the DPFE sensor.