EGR Valve....?

DOHC MARK VIII

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If you plugged the vaccum line to EGR Valve on a Mark VIII engine 93-96 model will it cause any problems? I'm having a cold start problem for the first two or three minutes and I'm wondering if it could be the EGR Value. Back in the "day" of the early emission cars, plugging the hose to the EGR Valve was a common fix :).

** Bill **
1995 LSC-R'ed w/Recaro's and Cobra R's
Veteran of Carlisle 2000/01/02
[a href=//cardomain.com/member_pages/view_page.pl?page_id=258112]For Pic's and Mods click here[/a]
 
RE: EGR Valve....?

I did and all I came up with was my post asking...or did you mean go to Carlisle?



** Bill **
1995 LSC-R'ed w/Recaro's and Cobra R's
Veteran of Carlisle 2000/01/02
[a href=//cardomain.com/member_pages/view_page.pl?page_id=258112]For Pic's and Mods click here[/a]
 
RE: EGR Valve....?

Thanks, Geno. Now to find a small ball bearing :).

** Bill **
1995 LSC-R'ed w/Recaro's and Cobra R's
Veteran of Carlisle 2000/01/02
[a href=//cardomain.com/member_pages/view_page.pl?page_id=258112]For Pic's and Mods click here[/a]
 
RE: EGR Valve....?

LAST EDITED ON Mar-26-03 AT 10:37 AM (EST) by Alexander (admin)

I did and all I came up with was my post asking...or did you mean go to Carlisle?

** Bill **
1995 LSC-R'ed w/Recaro's and Cobra R's
Veteran of Carlisle 2000/01/02
For Pic's and Mods click here

Sorry, Alexander. I didn't realize the "phrase" I used was obscene but I knew Steve would understand ;)

** Bill **
1995 LSC-R'ed w/Recaro's and Cobra R's
Veteran of Carlisle 2000/01/02
[a href=//cardomain.com/member_pages/view_page.pl?page_id=258112]For Pic's and Mods click here[/a]
 
RE: EGR Valve....?

I think the ECU will store some codes if the EGR isn't working right, but they are not codes that will light the 'Check Engine' light.

Is your IAC clean?
-Joel.
 
RE: EGR Valve....?

Since i put the other intake on my car, and unhooked the EGR, the check engine light comes after the car heats up. It will stay on for about 75 seconds, then turn off. Then after 5 minutes it will come back on. Somehow the car knows that the EGR is there, but not recirculating air back into the engine. HOW the computer knows this is beyond me. I cannot figure out how it would be able to tell.
 
RE: EGR Valve....?

DPFE? The Differential Pressure Feedback EGR sensor links with the PCM. I would speculate disconnecting the EGR vacumn causes a DTC because the PCM is issuing control to the EVR(EGR Vacumn Regulator) solenoid and expecting a certain 'feedback' via the DPFE.
 
RE: EGR Valve....?

Expanding further from the manual on the EGR system:


"The exhaust gas recirculation (EGR) system is designed to:

-Reintroduce exhaust gas into the combustion cycle.
-Lower combustion temperatures.
-Reduce the formation of Nitrous Oxide (NOX).

The amount of exhaust gas reintroduced and the timing of the cycle
varies by calibration. Timing and volume are controlled by:

-Engine rpm.
-Engine vacuum.
-Exhaust system back pressure.
-Engine coolant temperature.
-Throttle position.

The EGR valve (EGR valve) (9D475) is vacuum actuated. The vacuum hose
routing diagram is shown on the Vehicle Emission Control Information
(VECI) decal.

The EGR system is a differential pressure feedback EGR (DPFE) system.
DPFE is a subsonic closed loop EGR system. The DPFE system:

-Monitors EGR flow rate by the pressure drop across the metering
orifice.
-Uses an EGR pressure valve sensor (9J460) as the feedback device.
-Controlled pressure is varied by the valve movement using vacuum
output of the EGR vacuum regulator control (9J459).
-Uses the EGR valve only as a pressure regulator, rather than a flow
metering device.
-Allows for a more accurate assessment of EGR flow requirements."
 
RE: EGR Valve....?

Ahhh there is a sensor that monitors vacuum inside that EGR housing then.. That is how it knows that it is not hooked up right.

At any rate, the EGR makes the inside of you engine look like total crap.
As I understand the EGR was put on engines that had a higher amount of duration in the cams to compensate the added NOX emissions.

Seems like a small bandaid for a little power. At first when the engine is new it allows for more power, but as the engine gets more and more mileage/wear, the carbon builds up quite thick, actually hurting performance.

THat is why I took mine off when I put that pretty new intake/imrc's on. Plus I did not planning on running it with the long tubes.
 
RE: EGR Valve....?

I believe the EGR interacts with DPFE which in end controls fuel mixing and also interacts with temperature - you may end up with overheat conditions going lean/stalling going rich depending on strategy (startup/cold/warm/takeoff/idle). Try ISBN 0-8376-0301-3 Ford Fuel injection & Electronic Engine Control - Bentley Publishers for more info...

Christopher Bennett
Bristow, VA
93 Black LSC
 
RE: EGR Valve....?

Everytime i have had my car on the dyno it has been extremely rich. I need to get a chip that can take the EGR out of the equation and give the computer a constant number to work with at all times. Is this even possible?
 
RE: EGR Valve....?

In my previous reply I noted a book on sale, in that book are documented some racing (non-street) versions of EEC-IV which may fulfill your desire. I tink SVO sells them for NASCAR etc...

Christopher Bennett
Bristow, VA
93 Black LSC
 
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