EGR flow insuffiecent

babbster

babbster

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anybody ever get this code after a CEL. i have had it for over 7k miles. It doesnt seem to affect my performance at all but i would love to get the light off. Any help or suggestions would be appreciated.

I have a 2001 V6. EGR= exhuast gas recirculation...flow insuffiecent

thanks.
 
there is a tube coming off the passenger side exhaust that then connects into the EGR valve. There is a small vacuum line the then actuates the valve itself - allowing the gases in that tube to pass into the intake at high vacuum (idle).

There are two smaller tubes running off the exhaust-to-egr tube that goes into the DPFE - differential pressure feedback EGR - module which tells the PCM if the EGR is operating.

The code you are getting means that the PCM (via the DPFE) is not sensing flow through the tube (and through the EGR valve) at high vacuum (when the EGR should be open). So the DPFE is always seeing pressure as the exhaust fills the tube but the EGR is closed an not letting it flow into the intake.

so... could be:
- bad EGR valve
- vacuum issue not allowing the EGR to open
- DPFE module problem
- clogged tubes going to the DPFE
- clogged EGR tube
 
allowing the gases in that tube to pass into the intake at high vacuum (idle).
Click to expand...
I thought the EGR valve was supposed to remain closed at idle?

Its also pretty pointless to have the EGR open at idle as the combustion chamber does not reach high temps due to the richer mixture at idle.

As I understand it the EGR valve should only open when the engine is at a constant rpm above idle, when the throttle is open, as in highway driving.
 
dude - I over simplified it a bit - but you get the point - the DPFE is not detecting an difference in pressure between it's two sample tubes - meaning it does not see a flow in the EGR-to-intake tube - when it thinks there should be.

either the EGR vavle is not opening (valve or vacuum leak), the EGR tube is blocked, the DPFE sample tubes are blocked, DPFE is bad, ....
 
Im gonna take a look at it tomorrow so I can see everything your talking about. And hopefully from there I can visually see something being blocked if not I guess my only option is to start replacing things until I get it fixed. I have read up online about EGR problems, and it seems like quite a headache. Never really a straight forward solution to the problem. Thanks for all the input though.
 
ford has a TSB out for pretty much every obd2 car they make, saying any egr codes to replace the DPFE sensor, the exhaust constantly coming into contact with the electronics causes the sensor to fail, can you say condensation! call the dealer i think the sensor is about $50 bux (dont quote me) and also check the 2 hoses that run up to the sensor, they get brittle and crumble, dealer should have that stuff in bulk. the DPFE is easy to swap just be sure to keep track of what hose goes where on the sensor (its labeled on the underside, high and ref)
 
i have this exact same code guys...
what should be the "thing" to do?..
change the egr valve && replace the hoses?...
or is there more to it?

btw egr valve 35$ at autozone 78$ at orielly...
 
I'd take it apart and clean it first. EGR valves do get a fair amount of carbon built up on them over time. Which can easily be remedied with a tooth brush/ bottle brush and a can of brake cleaner. Either the valve itself, the hose leading to the valve from the exhaust, or the port into the intake manifold could be clogged and block the flow.

dude - I over simplified it a bit - but you get the point
Click to expand...
:p

I do, but if he goes hunting around under the hood and finds out that valve doesn't open at idle like you said, he's gonna think there's something wrong with it. When in fact it may be fine. Then he goes out and spends a bunch of money on a part that didn't necessarily need to be replaced.
 
I'm a little confused on how and where to take the egr valve apart...I know where its located but how do I remove it and what/where do I clean. Thanks for the help guys
 
you remove the two bolts on either side of the valve (which removes it from the manifold). Then loosen the nut on the EGR tube which then allows the valve to seperate from the tube (it can be tough - so get angry).

once off - clean it and test it with a vacuum gauge. Often it's a cracked vacuum line the prevents it from opening...
 
Im gonna pick up a new EGR valve from Autozone tomorrow for 34.99 and put it in this weekend. If the CEL goes away great, if not I guess I will go from there. Thanks for the help. I will update after I replace the EGR valve
 
well the guy at autozone suggested I clean the EGR valve instead of replacing it. so i cleaned it and the code came back. He thinks its the DPFE

"There are two smaller tubes running off the exhaust-to-egr tube that goes into the DPFE - differential pressure feedback EGR - module which tells the PCM if the EGR is operating",


Where is this located, near the firewall or towards the front of the car. Thanks
 
My understanding is that with Ford, it is usually the DPFE that is at fault. If you have a scope, you can tell by watching the voltage waveform from the sensor.
 
the DPFE is on the firewall passenger side - the EGR tube comes off the passenger exhuast manifold
 
babbster said:
well the guy at autozone suggested I clean the EGR valve instead of replacing it. so i cleaned it and the code came back. He thinks its the DPFE

"There are two smaller tubes running off the exhaust-to-egr tube that goes into the DPFE - differential pressure feedback EGR - module which tells the PCM if the EGR is operating",


Where is this located, near the firewall or towards the front of the car. Thanks
Click to expand...

funny you listen to the autozone guy, instead of the ford tech..........
 
its was alot easier for me to understand everthing when someone could point and explain everthing under the hood. I wanted to clean the egr valve first, which is free and then replace the dpfe is the clean egr didnt fix it. I will be replacing the dpfe tomorrow.
 
i know but you got lucky most autozone guys would rather sell you a egr valve than "help" you dont know how many people come to work asking me to install this egr valve autozone said i needed, i tell them to return it and ill fix the problem
 
chickenviii said:
i tell them to return it and ill fix the problem
Click to expand...

Silly chicken.

Fit their silly valve... then, when it doesn't fix the problem... charge out of book time to diagnose and fix correct problem! LOL.

Result: chicken: :p

Customer: :(
 
i had a guy with a f150, i put 3 autozone power steering pumps on it in 2 days, then he bought a ford one. and trust me he got charged everytime i R&R'ed one. the egr valve can be a PIA on some cars, then you break the tube.......welcome to hell. my foreman at work says "work smart, not hard"
 
Yeah, i was just thinking about if you had a slow day and wanted to extract maximum $$$ from a customer who acts like a jerk. Getting cynical in my old age! Lol.
 
I replaced the dpfe today. not much to it just kind of difficult to get to. So far the check engine light is gone, hopefully it will stay that way.
 
Well unfortunatly my CEL came back on today after about 55 miles with it off. Im going to double check all the connections but if everythings fine I guess i need to replace the tubes bc maybe they are blocked up. Any further ideas or suggestions would be beneficial. Thanks. Im also gonna have the code read to make sure that its the same problem that came back and not something different.
 
usually its either the sensor (99.9%) or the hoses are shot, and i did have one case where a mouse chewed through a wire
 
My 2001 V6 sport had the same problem recently (EGR insufficient flow) - my local garage assumed the DPFE as well (after checking that the actual EGR value was working correctly and not clogged or jammed). They changed out the DPFE and, of course, the CEL came back on after just a few miles.

In my case, the actual reason for the problem turned out to be the throttle body itself - the EGR hoses connect to the throttle body (that's how the recirculated exhaust gases get back into the incoming air) and the little machined orifices were partially clogged. A thorough clean of the throttle body fixed it for good, so in all likelihood I also paid for a DPFE sensor that I did not need.

Check the throttle body assembly!!
 
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