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EGR flow insuffiecent

babbster
September 28th, 2008, 06:32 PM
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.

lincoln00
September 28th, 2008, 07:28 PM
clean or replace EGR

Quik LS
September 28th, 2008, 07:58 PM
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

97stscaddy
September 28th, 2008, 08:20 PM
allowing the gases in that tube to pass into the intake at high vacuum (idle).
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.

Quik LS
September 28th, 2008, 08:31 PM
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, ....

babbster
September 28th, 2008, 09:07 PM
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.

chicken
September 29th, 2008, 07:56 PM
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)

slabls
September 30th, 2008, 06:58 AM
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...

97stscaddy
September 30th, 2008, 06:13 PM
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 :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.

babbster
September 30th, 2008, 07:45 PM
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

Quik LS
September 30th, 2008, 08:00 PM
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...

babbster
October 1st, 2008, 09:35 PM
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

babbster
October 6th, 2008, 02:24 PM
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

joegr
October 6th, 2008, 03:33 PM
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.

Quik LS
October 6th, 2008, 04:00 PM
the DPFE is on the firewall passenger side - the EGR tube comes off the passenger exhuast manifold

chicken
October 6th, 2008, 10:09 PM
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

funny you listen to the autozone guy, instead of the ford tech..........

babbster
October 6th, 2008, 10:31 PM
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.

chicken
October 6th, 2008, 10:51 PM
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

Aquabrit
October 6th, 2008, 11:00 PM
i tell them to return it and ill fix the problem

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: :(

chicken
October 6th, 2008, 11:26 PM
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"

Aquabrit
October 6th, 2008, 11:35 PM
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.

babbster
October 7th, 2008, 04:27 PM
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.

babbster
October 8th, 2008, 11:51 AM
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.

chicken
October 8th, 2008, 06:39 PM
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

StanE
October 9th, 2008, 09:04 PM
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!!

slabls
October 9th, 2008, 09:36 PM
throttle body assembly location anyone?...

chicken
October 9th, 2008, 10:54 PM
the tubes to and from the dpfe go to the egr tube and only the egr tube.

LsUnV2
October 9th, 2008, 11:02 PM
throttle body assembly location anyone?...

its in the trunk next to battery. jeesh:lol:

Quik LS
October 10th, 2008, 05:48 AM
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.

This is not correct. the EGR valve is mounted into the intake manifold directly - no hose.

Are you sure you were not talking about the PCV tubes?

babbster
October 10th, 2008, 08:10 PM
Well when my CEL came back on I had the code checked to make sure it was the same code. Ironcly the code had changed from EGR flow insufficient to EGR flow excessive. I started looking for some lose tubes or bolts. The egr valve appeared to be lose from the manifold. I pulled it off replaced the gasket and tightened back on as tight as I could. Car now feels fixed and drives fixed and IS fixed. CEL is gone for about 150 miles. That plus a free tune from an unlocked LIVEWIRE and my car drives great. Thanks for all the help.

slabls
October 11th, 2008, 11:12 PM
its in the trunk next to battery. jeesh:lol:



:dancefool

slabls
January 8th, 2009, 04:51 PM
how in the hell do you get the egr valve off??

i took the 2 bolts or screws out...i've tried twisting it off but it seems like its stuck forever...

please help asap!!!

Quik LS
January 8th, 2009, 07:20 PM
yep - common issue - the exhuast crap seizes it all up.

Use a 'big' wrench. If that does not work - use PB Blaster.

Do not use WD40 - the silicon in it is not sensor safe.

SPSully
January 8th, 2009, 10:21 PM
hmmmm... Sounds like a perfect job for a BFH!!!!!!!!! then do an EGR delete so you dont have to worry about the damage done to sensors.

Quik LS
January 8th, 2009, 11:05 PM
think of the baby seals.


plus you have to knock out the EGR with SCT our it will throw a CEL...

SPSully
January 8th, 2009, 11:10 PM
think of the baby seals.


plus you have to knock out the EGR with SCT our it will throw a CEL...

BAD IDEA!!!!!!!!!!!!! There is no way the plasticc case of the SCT can withstand the impact! :p

Quik LS
January 8th, 2009, 11:26 PM
not your good one - I beleive lincoln00 has one for sale.

phase_one
May 15th, 2009, 08:41 AM
Having similar problems thanks for all the info.

mharrison
May 15th, 2009, 01:34 PM
Just to add to this, while doing valve cover gaskets and replacing the PCV hoses (what a PITA), I damaged my EGR valve gasket while removing the EGR from the manifold and when it was back together I began getting this CEL Code. A new EGR Valve Gasket fixed my CEL.

oddball
November 14th, 2010, 10:41 PM
In case anyone hits this on a search.....
For my '02 V8 w/ 150k, I did a ton of work a few weeks ago. The bracket that the EGR valve mounts onto - sits between the valve and the intake - has a tube that extends into the intake. Mine was almost entirely clogged with gunk. Some Simple Green and elbow grease cleaned it up.
So, clean the EGR AND the mounting bracket. Take it off the intake to clean it.....

JennsLincolnLS
April 17th, 2011, 01:27 AM
I couldn't for some reason find this post earlier when I was looking for egr solutions....but thanks to all of you, I know now that I probably bought an egr valve that I didn't need, from now on I'll ask you guys first you seem to know what's up. And hopefully I do not need to replace the egr selonoid....I hope someone can help me out with that....and that I am doing OK with how I am attempting to fix my car.
Thank you,
Jennifer

cammerfe
April 17th, 2011, 12:36 PM
The mass of information in this thread should be made into a sticky!!

KS


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