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I'm just wanting to do something like unplug the EGR valve if it defaults to the closed position. I'm willing to put up with a Check Engine Light for now, until an engine tune is available.
I wouldn't do that.

I tried doing this with my TDI. Forced the valve closed with Ross Tech software. The ECU retarded the ignition timing and made it run like ****, lost about 10 MPGs.

You would need to re-map the fuel and boost to take advantage of the extra O2 in the clean airstream.
 

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Ignition timing? You're using terms from spark ignition engines.

Diesel engines run O2 rich at all times of operation. EGR is used to reduce O2 content to avoid NOx production. A total elimination of EGR means the same amount of fuel is being injected (if you didn't change fueling) and there should be no change in operation other than avoiding your intake being sooted up with exhaust gas.

There has to be something else going on with your TDI tuning.
Sorry Barry, I mis-spelled injection timing, but spell check corrected it to ignition.

Regardless of the spelling error you should know what I'm talking about. All modern diesel are common rail systems where fuel injection and duration is controlled by the ECU related to load and crank angle position.

On my TDI, I manipulating the EGR valve to closed position. As a result, the ECU adapted by retarding the injection timing. Not sure about duration. I can say that it ran like S--- until we restored the degree function of the EGR. After that it was back to normal.

The TDI ECU will react to a change in EGR flow and adjust timing, which is what happened. This is well known to most tuners, however, like you, I thought it could be easily changed to improve efficiency. Unfortunately, this was not the case.

These new diesels are not like the old ones where timing was controlled by the IP. The new Cruze diesel engine is more sophisticated than my TDI was, it even has VVT. So I'm sure you will also have a similar experience. The ECU will need to be re-tuned to operate w/out any EGR and de-fueled for you to take advantage of the extra O2.

That's the reason I do not recommend you do meddle with the EGR valve. I suggest you contact Green Diesel Engineering and ask them to create a ECO tune for this engine. If they get enough of a response, it may happen.
 

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Hi there,

I too am looking for a solution to this. Green Diesel Eng. seems to be the most hopeful promise. I've visited up there a few times already and brought it to their attention there is a market for that tune. My Dad own a '14 Ecodiesel by RAM. Hauls TT, Airstreams, Boats, Cars with it as a business. Has the EGR tune they offer for it, loves it, no trouble with it at all. 450k on the truck so far - guy's a madman. Moderates for https://www.ram1500diesel.com and loves all things Ecodiesel. He turned me on to the Cruze TD as an option for my business. Fingers crossed we get our version of the tune with a warranty on it sometime soon.


All The Best,

Gabriel
I guess your dad got one of the few good Ram Ecodiesels. I wouldn’t buy one of those things for 50% off retail.

I created a post asking about an Eco tune for the Cruze 1.6L on the Green Diesel forum about a month ago. I suggest you guys create profiles and “pile on” to the thread, post “I’m in” or something so they can gauge interest.
 

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What's needed is to have a tune to set the EGR to a Dynamic operation = less of it, alot less.
1. Break ECU encryption.

2. Throttle EGR valve operation.

3. R & D. Lean out fuel maps and boost curves for new parameters excluding the influence of EGR.

4. Alter DEF dosage using limits or forced values. Otherwise higher NOX values with cause DEF usage to be ecxessive and eventually damage the SCR.

You’re better off contacting the tuner I mentioned earlier who has the resources to do do all this stuff as it is beyond the capabilities of most people.
 

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Perhaps only if it's excessive related to the amount of exhaust flowing through it (and thus, NOx).

There are NOx sensors before and after the SCR that would adjust the amount of DEF in accordance to the NOx "content" of the exhaust gasses.
Yes, but you fail to realize that by tuning the ECU and disabling EGR, NOx concentrations will increase substantially as you will have a leaner mixture and and more complete combustion. As a result of complete combustion, less soot is generated so the Regen time between DEF cleanings will increase.

You will not be able to treat the exhaust with the SCR so it’s best use forced values or disable it completely.
 

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Pre-SCR NOx sensor would pick that up and use extra DEF to bring the post-SCR NOx reading down back to what it wants. Like I said before.

You’re assuming it can. It’s speculation. Nobody knows if it’s possible because the SCR was never designed as primary treatment for NOx, and at higher concentrations than it would ever see otherwise. It is a secondary treatment after EGR. Do you think GM would engineer the extra capacity to treat NOx at 300% or more of normal in the SCR? I seriously doubt that would be cost effective under current “value engineering” principals used in manufacturing.

You can contact GDE and ask get their input on What may be possible. You can also put pressure on them to develop a tune for the Cruze.
 
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