EGR question?

DOC4444 · **Posted:** Sun Jun 15, 2008 9:15 pm

I gather that it has been established that the european EGR setup is different than the US, but I have not found anything about those sent to Aus/NZ.

DOC

MACKJ · **Posted:** Sun Jun 15, 2008 9:29 pm

DOC4444 wrote:

I gather that it has been established that the european EGR setup is different than the US, but I have not found anything about those sent to Aus/NZ.

DOC

Exactly. All the photos I have seen show them as being the same. I also know some of the guys over here have purchased the SEGR, so I ask again, what proof does anyone have they are different?

nursecosmo · **Posted:** Mon Jun 16, 2008 3:44 am

Turbo Tim wrote:

I’m confused. If you block off the EGR and take the plate off of the AFC valve, you say that the computer is happy since it thinks everything is connected and working?

How is that different from a plugged up EGR valve with soot?
The computer is expecting a change in the MAF flow when it fires the EGR valve.
How does it know it is not plugged up with soot instead of a block-off plate?

If you plumbed the EGR to the outside air, that won’t work as with the backpressure on the turbo exhaust is much greater than the intake manifold pressure. When the EGR opens it would vent boost out instead of sucking air in.

Have you done this to a CRD and got no CEL?

I can't find the earlier post that I'm thinking about but I belive the gist of it was that the ECU monitors the current draw during EGR actuation and can tell how far the solenoid moves, or if it does not move, as in a plugged EGR. If that is indeed the case then a blocked off EGR valve would not throw a code. I might try that as soon as I get the time to work on it and see if it works on Jeeps with the steering wheel on the left (correct :wink:

) side.

Turbo Tim · **Posted:** Mon Jun 16, 2008 11:38 am

Nope, the computer does not know how far or if the EGR moves. It “Measures” the current to activate it and figures that it is connected. Too much current = shorted = Bad, no current = Open = Bad, if it draws about 1.2 Amps = connected = Good, Pass.
The next step for the computer is to fire the EGR and watch how much the MAF signal decreases. No decrease or not enough decrease for a given pulse width = Bad EGR or plugged up with soot EGR = Bad = Fail and CEL light.
Note that this is done in two steps. EGR “On” is part 1 and MAF “Should” decrease some. Next it will fire the AFC in steps and MAF better start decreasing rapidly or EGR system = Bad + CEL.
For both AFC and EGR the computer controls the pulse width or how long it is told to turn on. This is the way it controls how much EGR is put in. Sort of like a water valve, turn it on and off in quick pulses or open it up all the way.

nursecosmo · **Posted:** Tue Jun 17, 2008 12:34 am

Turbo Tim wrote:

Nope, the computer does not know how far or if the EGR moves. It “Measures” the current to activate it and figures that it is connected. Too much current = shorted = Bad, no current = Open = Bad, if it draws about 1.2 Amps = connected = Good, Pass.
The next step for the computer is to fire the EGR and watch how much the MAF signal decreases. No decrease or not enough decrease for a given pulse width = Bad EGR or plugged up with soot EGR = Bad = Fail and CEL light.
Note that this is done in two steps. EGR “On” is part 1 and MAF “Should” decrease some. Next it will fire the AFC in steps and MAF better start decreasing rapidly or EGR system = Bad + CEL.
For both AFC and EGR the computer controls the pulse width or how long it is told to turn on. This is the way it controls how much EGR is put in. Sort of like a water valve, turn it on and off in quick pulses or open it up all the way.

If this is the case then why do the non operable butterflys (either worn out or with the gears intentionaly removed) in the FCV not throw a cel? Inquireing minds need to know.

Turbo Tim · **Posted:** Tue Jun 17, 2008 9:16 am

Vehicles with a turbo have a much higher exhaust “Back Pressure.” Most turbos run at a pressure ratio of about 1½ to 1. In other words, if you have 10 PSI of intake pressure, you will have 15 PSI of exhaust back pressure. Nothing is for free.
So if the EGR is not loaded up with soot, the passage should be fairly open. This means that the 15 PSI of exhaust can easily flow into the 10 PSI of intake pressure. I believe that the AFC is only used for a few exceptional EGR conditions and also there for the smooth shutdown.
One could remove the AFC connector and stuff a 1 K Ohm resistor in the connector (signal to 12 Volts) and the computer would not know the difference.
If there were some special EGR condition where it needed max EGR and the MAF signal doesn’t decrease, it will throw a CEL. Again the EGR system is two parts, the EGR and the AFC.

Sir Sam · **Posted:** Tue Jun 17, 2008 11:06 am

MACKJ wrote:

Sir Sam wrote:

MACKJ wrote:

DOC4444,
I have had the vehicle in for at least one major service and some warranty work on another occasion since the mod and they have not noticed anything. The only thing anyone would notice, if they were looking for it, is the slightly rougher shutdown.

Tim,
I beg to differ...as I mentioned in my earlier post we pretty much follow California's lead on emissions control so I am guessing our EGR systems are identical. Physically they are plumbed up the same and, as I said, someone needs to try it to prove me right or wrong.

Your EGR setup IS NOT the same as the US.

OK what is the difference?

The difference is in your solenoid and actuator setup, but you are right unplugging the MAF on a aus 05-06 has the same result as the US.

And of course, the 02-04 is different as well.

DOC4444 · **Posted:** Tue Jun 17, 2008 11:13 am

Sam,

So do the "differences" suggest to you that Mack's approach will or will not work with a US CRD?

Thanks,

DOC

Sir Sam · **Posted:** Tue Jun 17, 2008 11:27 am

DOC4444 wrote:

Sam,

So do the "differences" suggest to you that Mack's approach will or will not work with a US CRD?

Thanks,

DOC

I don't see why it wouldn't.

The systems work the same way, the differences that exist are basically semantics. The ECU however is in fact programmed different, in terms of duration, rpm etc, that see EGR use. Lower emissions standards less EGR time.

ThorCRD · **Posted:** Wed Jun 18, 2008 12:20 am

If I get the SEGR kit, is there anyone in the Castle Rock, Colorado area that may be willing to help (that has done one). Could I bribe anyone with a case of Suds?

DOC4444 · **Posted:** Wed Jun 18, 2008 10:05 am

So, anybody willing to step up and try Mack's approach on a US CRD? (I would, but work has me going 7 days for the next several weeks.)

DOC

MACKJ · **Posted:** Thu Jun 19, 2008 4:42 pm

DOC4444 wrote:

So, anybody willing to step up and try Mack's approach on a US CRD? (I would, but work has me going 7 days for the next several weeks.)

DOC

I have just been told by one of our US members (who shall remain nameless) that the mod works, no CEL.
OK, so who is next to step up to the "plate" ?

UFO · **Posted:** Thu Jun 19, 2008 5:43 pm

ThorCRD wrote:

If I get the SEGR kit, is there anyone in the Castle Rock, Colorado area that may be willing to help (that has done one). Could I bribe anyone with a case of Suds?

I'm in Denver, and have built and tested 50+ kits. I've also installed my own and helped another install theirs.

MTB_TDI · **Posted:** Thu Jun 19, 2008 6:48 pm

MACKJ wrote:

DOC4444 wrote:

So, anybody willing to step up and try Mack's approach on a US CRD? (I would, but work has me going 7 days for the next several weeks.)

DOC

I have just been told by one of our US members (who shall remain nameless) that the mod works, no CEL.
OK, so who is next to step up to the "plate" ?

I may have to talk to my friend and see if he is willing to do this. The only down side is the shut down. There are few good sides to this, your coolant won't heat up as much, and no EGR. Oh, and cost!!

Anomious · **Posted:** Sun Jun 22, 2008 3:10 pm

UFO wrote:

ThorCRD wrote:

If I get the SEGR kit, is there anyone in the Castle Rock, Colorado area that may be willing to help (that has done one). Could I bribe anyone with a case of Suds?

I'm in Denver, and have built and tested 50+ kits. I've also installed my own and helped another install theirs.

Hi! I have an unused SEGR kit for sale, $50+shipping.

Also have a Cat 2u fuel filter kit foe $30+shipping

L.

EGR question?

Who is online