Eskimo1

Figured my efforts might warrant their own post. Here's what I initially noticed (Copied from the emissions thread):
I got Torque to work with my crappy old OBDII adapter, and was able to see EGT's, DPF pressure, boost, etc. Since my '16 is currently bone stock and un-fixed, this will be some good baselines.

Problem is, I don't have a frame of reference as to what "OK" EGT's are for this particular engine. My last diesel was a 12-valve Cummins, and with the EGT probe mounted several inches away from the (iron) head, the goal was to keep EGT's at or below 1200°. Brief spikes higher than that were OK (I pegged the 1600° gauge on a dyno pull), but for all-day towing, 1200° or below. Duramax guys (with their aluminum heads) were more liberal in their "safe" EGT's, normally saying something more like 1350-1400° is OK. **EDIT: It would appear the DME de-fuels at 1450°**

Doing a brake-launched 0-85mph pull in the CD yesterday, EGT's stayed at 1200-1300, and slowly climbed to a peak of ~1400° (Perhaps that's where the ECU starts de-fueling?). I've also realized why they don't give us a boost gauge - it's all over the place! Did see a peak of 37psi right at launch. As suspected with this small, responsive turbo, either mechanically or electronically, boost falls off at higher RPM. When I get a little time, I'll turn on data logging and get some of this in a CSV for those interested.

After driving around a bit more with the dashboard running (and this mirrors my previous experiences with a 5.9L Cummins), I can predict that EGT's will be FAR more affected by the gear you're in than whatever change they make to the DME. I'll even go so far as to say that the reports of the car downshifting more easily post-fix will mean that EGT's should be lower. 2

Example: I roll into the throttle as far as I can go without downshifting at <1500 RPM. The EGT's shoot up quickly before the turbo spools. This behavior is certainly dumping quite a bit of soot into the DPF. Once the turbo spools and boost comes up, EGT's go down. Keeping the RPM's between 1600-3200 really seems to make it impossible to get high EGT's - not surprising given the performance curve of the engine and where the turbo is happiest.

I'm dropping the CD at the dealer for the fix on Tuesday evening, so I'll log the loop today. Post-fix logging on the loop will have to wait until next weekend. The loop will start with a "cold" start (45° in my garage), some downhill to a stop, 4 miles of 45mph 2-lane roads with some mild hills, 1 mile of driving near the interstate, 8 miles of interstate (I'll set the cruise at 75 or so), 1 mile of 4 lane, 2 miles of mostly slight uphill 2-lane, ending with 1/2 mile of a decent uphill. I'll use cruise control as much as possible, and won't use Sport mode (since Sport keeps a lower gear typically, lowering EGT's).

I'll log:
g-sensors
DPF pressure (I have no idea what this should be, but it's there)
Trans Temp
Boost
EGT
RPM
Speed
Coolant temp
Throttle position if I can get it to read properly.

****PRE-FIX:
raw CSV: https://drive.google.com/open?id=1Wb...lE8Kj8Bmf8Z-E9
Excel with graphs: https://drive.google.com/open?id=18W...ah7aKM4utdJeTb

****POST-FIX:
raw CSV: https://drive.google.com/open?id=1TX...L8HA43Q-Kv6zPS
Excel with graphs: https://drive.google.com/open?id=1vQ...Aydl5ON1At2oka

visitador

Thanks for doing this! Greatly appreciated

skiahh

2nd this!

And it definitely warrants its own thread. Good call!

Eskimo1

Here's a link to the CSV and an Excel version that I cleaned up a little and took a stab at graphing. A few things I noticed:

I couldn't get a good throttle position readout. Might need some custom PID's? That would be really useful to help give an idea of what I was doing.
the G-sensors didn't work. I bet there are some PID's to read off the car's sensors.

Here's the raw CSV: https://drive.google.com/open?id=1Wb...lE8Kj8Bmf8Z-E9
Here's the Excel: https://drive.google.com/open?id=18W...ah7aKM4utdJeTb

Unfortunately, I probably won't get a chance to re-do this with any additional channels before it goes in for the fix.

Eskimo1

Post-fix graphs added to the first post.

Cliff's notes: EGT's are lower post-fix because of running in lower gear.

skiahh

Thanks, Eskimo... they really don't look all that different, overall.

visitador

Thank you too. Looks to me the issue about EGT is not that significant. Maybe the more knowledgeable members can interpret the data better?

skiahh

I'm guessing the data was derived using a warm engine, so the missing info is what does the data look like while the engine is warming up.

But it doesn't look like 3000 rpm is producing any real spikes in EGTs, either. Unfortunately, we don't see any sustained operation at 3K rpms, so hard to tell anything on that from this data.

Eskimo1

I was very careful to start logging when cold.

skiahh

Even better!

RS-America

Thanks for getting hard data points and posting!
We are still undecided about getting the 'fix'. I have posted pre 'fix' dyno numbers for our '13 diesel. Would really like to see someone post their '13 or '14 dyno numbers after getting the 'fix'. Expect the '15 and '16s to preform differently as their 'fix' is different. Many speak of feeling no change or some change butt impressions are hard to correlate into hard data. (pun-intended)
Would complete the picture if someone would also get Pre & Post-fix dyno runs for both a 13/14 and a 15/16 CD. We have a 2013 CD and got a pre dyno run - Here are our before -at the wheels- numbers run on a Dynojet with data normalized for temperature.

Max Pwr______203.20____200.97_____202.42
Engine RPM____3.55______3.56_______3.54
Max Trq______354.82_____356.82____352.35
Engine RPM___2.46_______2.44______2.42

Still not convinced to get the 'fix' - Would like to see numbers after the 'fix' - We do endurance off-road rally & Overlanding, can not afford to give up performance. One run last summer started at 3800' climbed to 8000' then descended to 4000' in less than one mile.
Another potential issue for us is cold weather starts as in the -36F it got to in Yellowknife. Has anyone had the fix in the north, how has it started in sub-zero temps?

On a positive note I did see a photo of the new and old hard wear that is being replaced on the '13 & '14s. The inlet design looks like it is an improved design.
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Eskimo1

How much power loss are you worried about? If there was any appreciable loss, it would have bubbled up by now. Just my opinion, but I think you're worried about basically nothing. Same with cold weather starts. If anything, it warms up faster now. The actual starting cycle would be unaffected.

docwyte

Supposedly, by law with the EPA, performance and gas mileage couldn't be affected by more than 2%.

If any of us can detect a 2% difference, I'd be very impressed. Most dynos have an degree of error larger than that

GrandPaJohn

I keep asking myself....if the "fix" was this simple and doesn't affect performance, why did they cheat in the first place?

BenCD

Because like most every criminal out there, they never thought they'd get caught.

The condensed version: The engineers could not get the motors to meet the emissions standards at the time, but could based on the tests being conducted at the time, but they had to use a "device" or software that was developed by Bosch-and is why they are implicated/complicit in the deception and why FCA is now in trouble with their EcoDiesels. As time went on, the engineers got closer and closer to being able to meet the requirements but the company decided that because their cheat was working, that it would be worth it to keep cheating and pay whatever fine if they got caught. Their gamble did not pay off and are now into it for something like 30 Billion USDollars.

It is the 1st generations of the TDI's that could not be fixed and had to be bought back. The later gens can be fixed enough to let us keep driving them.