6.7 EGR Servo Motor Mod??

[IdleUp]

OK someone posted some great images of the ERG delete on his truck, there presently is three movable valves;

1) The valve with the servo motor & cables sitting by the heater tank for the crossover tube.

2) The EGR valve on the other end of the tube.

3) the large valve on the intake side coming from the intercooler.

My concern is just stopping the flow of exhaust gas to the engine so the large valve going to the intercooler should not be a problem - it would seem to me we could just unplug the two valves on the crossover to accomplish this.

Thanks

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2008 3500 Resistol 6.7 Bone Stock
www.bigpickup.com
www.rotory.com

[Shibbyutman]

OK to clarify:

EGR Valve (on the intake horn) controls the FLOW of the EGR into the intake.
Throttling Valve (below the intake horn) controls the RATIO of EGR to fresh air.
The Bypass Valve (on top of the ext manifold) controls the TEMPERATURE of the EGR into the intake.

Messing around with the bypass valve with do NOTHING to stop the flow as it will just pull either hot or cold depending on the position. To stop the flow you need to block the egr. Also agree with Gary here, you need to watch out if you just unplug the egr as it can very well just blow open and STAY open because there is nothing to return it. Best option yet is to get the plates and remove the valve itself. The 6.7 ECM is very picky about what it wants to see and is making it difficult to delete the whole system.

__________________
2003 Dodge Ram 2500 4X4, Banks Big Hoss Bundle, K&N FIPK, 5" Turbo back Expand-It exhaust, Goerend Full Built Trans, Smarty REVO, DIY Fuel Control Actuator Mod, FASS 150/150 and custom big line kit.ABS Brake Specialist-You've got questions, I've got answers.

[IdleUp]

Here's some images from one of our users - regretfully i just copied them and failed to bookmark the thread so thanks to that user whom ever he may be.

I'm not sure the large valve on the intake to the intercooler has much to do with the EGR since on most large engines do not restrict the intake. Can't understand why they would want to choke or restrict the intake unless that's for a runaway should the RPM get to high, the ECU could just shut down the engine here regardless of what the fuel was doing. Anyhow it's over my head maybe one of the sharp shooters on the Forum would know.

From what I've read, the EGR really does not mix any exhaust in the intake unless the engine is working so for general easy driving (I would guess) the crossover tube is just static.

If either valve is closed (EGR or Servo) then the engine runs clean which means higher MPG and the maybe dirty turbo problems are over as well.

Unlike disassembling the crossover tube and plugging it - If we can just unplug either the EGR or the Servo so they remain closed we cure the problem and there is no way Cummins can prove the system is altered.

Since I'm sure that Cummins has to be working on a solution for this problem. I'm not ready to give up my warranty since they will no doubt have to come up with a fix which might include a new Turbo design and or a modified EGR system that will fix the the turbine problem.

What do you guys think?

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2008 3500 Resistol 6.7 Bone Stock
www.bigpickup.com
www.rotory.com

[LSmith]

I'm pretty sure the solution you are suggesting has been tried and the result was hard codes being set in the computer and a subsequent trip to the dealer.

The butterfly valve in your top pic has to be removed because if you just unplug it, the engine doesn't run right -- and the concern about the EGR servo is the pressure from the exhaust blowing it open if there is no signal to keep it closed.

Now, having said that, IF you knew the pin-out of the connector and could determine which pin told the butterfly to stay open and the EGR to stay closed, you may be able to make it work -- I don't know. I do know the EGR is capable of staying closed against the pressure when it's being told to do so by the ECM so it would stand to reason if you "hot wired" it closed, it would stay closed. We know unplugging the EGR just sets a soft code and leaves the truck driveable. If you unplug the butterfly, you may get a hard code. If they were hot-wired, they would have to be unplugged from the harness.

There was also some concern about condensation build up inside the EGR and bypass if they were left in place and no air were actually moving through them.

The bottom picture you posted is of the valve that controls whether the exhaust goes through the EGR cooler or not -- it doesn't come into play here.

BTW: the pics are from Compcowboy's sticky at the top of the Performance section

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2007.5 2500 4X4 Quad Cab 6.7L
Len

[IdleUp]

LSmith,

Thanks for shedding some light on the subject - I guess our only choice is to walk the line and we'll have to make the decision for what's best for our trucks, or to keep being a test bed for Cummins if we want to keep our warranty.

Hopefully Cummins will come up with a fix for this nightmare and if they don't, we'll all be looking for after market delete kits.

I do have one question, on the bottom picture where the flange goes to the ERG cooler valve - if we were just to plate that (block it off at the flange) and leave all the rest hooked up and plugged in, what do you think the results would be concerning codes?

__________________
2008 3500 Resistol 6.7 Bone Stock
www.bigpickup.com
www.rotory.com

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Last edited by IdleUp : 06-29-2008 at 04:42 PM.

[Compcowboy]

not sure what you would gain from that. If you wanna leave a stock appearance then you can use thin plates as well as a thinner disk to put in the crossover tube. You will need to leave the EGR valve unplugged for daily driving but if you go back in just plug it back in. Regardless the butterfly valve must come out unless you can hot wire that valve open all the time, but then you are tampering with the factory wiring and they might spot it.

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??? Hp ???? Tq - 2007 6.7 TWIN TURBO 2500 Bighorn 4x4 6-spd Manual, Airdog 150, ARP Head Studs, Bullydog PMT, TS MP-8, Airbags with Dual Control Air Comp., H&S Delete & Downpipe, What EGR?, Valair Dual Disk, Amsoil Bmk-11 Bypass, 295/70/R17 Toyos on Walker Evans Wheels,6" Aussies & Hushpower Muffler & DiProcol Gauges & 120HP nozzles (on the way) Thanks to Wally At FTEDiesel!!!!!

[LSmith]

If you blocked it off and left everything else plugged in, when the EGR was commanded to open, the Throttling valve would attempt to adjust the clean air flow down to compensate for the expected exhaust air coming through the EGR. That's when the surging that everyone talks about starts. The engine is expecting a certain amount of air (clean or not!) and when it doesn't get it, it ain't happy. Also, based on what I understand, the EGR is open most of the time. Exceptions are during a Desoot regen and when the EB is open. I think the other two types of regen allow a percentage or EGR, but not 100% open.

If you just block off the end on the exhaust side and go ahead and unplug the EGR and remove the butterfly, functionally, it should work fine. The logic was moisture could build up and cause damage in the form of corrosion to the EGR servo thus preventing you from ever putting it back to stock.

Everyone is scratching their heads on this trying to figure out a more simple solution. As of now, it seems that the EGR delete method described by the pictures is the only proven solution. Personally, I would like a different one too, but I'm not ready to start cutting wires on my truck --- yet.

__________________
2007.5 2500 4X4 Quad Cab 6.7L
Len

[LSmith]

Compcowboy types faster than me

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2007.5 2500 4X4 Quad Cab 6.7L
Len

[IdleUp]

Ok thanks guys - at least it seemed like a good idea!

__________________
2008 3500 Resistol 6.7 Bone Stock
www.bigpickup.com
www.rotory.com

[Shibbyutman]

Also if you want to unplug the egr valve it isn't just one wire that would need to be plugged in to allow it to power the EGR shut. It is a stepper motor that controls the position of the valve via a machine screw thread.

__________________
2003 Dodge Ram 2500 4X4, Banks Big Hoss Bundle, K&N FIPK, 5" Turbo back Expand-It exhaust, Goerend Full Built Trans, Smarty REVO, DIY Fuel Control Actuator Mod, FASS 150/150 and custom big line kit.ABS Brake Specialist-You've got questions, I've got answers.

[LSmith]

So all 8 wires are just for positioning? Do you have the pin out?

__________________
2007.5 2500 4X4 Quad Cab 6.7L
Len

[slagburn]

ASSEMBLY-EGR VALVE8 WAY CAV CIRCUIT FUNCTION
1 F855 18PK/YL 5 VOLT SUPPLY
2 K687 18DB/LB EGR SIGNAL NO. 3
3 K685 18DB EGR SIGNAL NO. 2
4 K683 18DB/GY EGR SIGNAL NO. 1
5 K916 18BR/OR SENSOR GROUND
6 K686 18GY/DB EGR CONTROL NO. 3
7 K684 18DB/YL EGR CONTROL NO. 2
8 K682 18DB/WT EGR CONTROL NO. 1

VALVE-EGR AIRFLOW CONTROL4 WAY CAV CIRCUIT FUNCTION
1 K158 18BR/YL EGR AIRFLOW CONTROL VALVE MOTOR (+)
2 K314 18BR EGR AIRFLOW CONTROL VALVE MOTOR (-)
3 F348 16PK/OR SMART POWER RELAY FEED
4 K971 18BR/PK SENSOR GROUND

VALVE-EGR COOLER BYPASS4 WAY CAV CIRCUIT FUNCTION
1 K671 18BR/DB EGR BYPASS STATUS
2 K670 18BR/LB EGR BYPASS VALVE SIGNAL
3 F348 16PK/OR SMART POWER RELAY FEED
4 K972 18DB/TN ACTUATOR GROUND

per the manual.

__________________
07.5, 6.7, Auto, QC, 4x4, Lots of gauges - ISSPRO (Pyro, Boost, Trans Temp) PriCol Optix (Fuel Pressure Lift/Rail) AutoMeter (Oil Pressure) - Dynatrac Free-Spin Hub Conversion Kit - RETRAX bed cover - homebrew shaved bluetec badge - plugged up EGR - Baldwin BF1212 water separator and CAT 1R0750 fuel filter - MSD Dashhawk - Baldwin B164 Bypass Filter

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Last edited by slagburn : 06-30-2008 at 05:05 PM.