Playing around with the 2.7 software (ECU and TCU)

[Adrian D]

Originally Posted by RTB

Speaking of EGR. I have read some advice that the Start Of Injection (SOI) map is created in such a way by the OEM that it adds advance to the SOI during periods of EGR flow. The recommendation is that if modifying EGR, then the SOI should also be reduced as EGR creates a longer burn time. Without EGR it was suggested this should be reduced.

Something similar does appear to be visible in our SOI maps.The area in the red line does not follow the same pattern as the rest of the map. Looks to be a mid area of greater injection advance.

What is your experience with this? Also, do you know what the horizontal axis is in the SOI? Vertical looks to be fuel rail pressure.

Here's a short discussion on ecuconnections, specifically the post by juice
https://www.ecuconnections.com/forum...f44be&start=50

I think it would make sense to reduce SOI once the EGR is off, really curious how it behaves.

Here's another good read:
https://www.ecuconnections.com/forum...ic.php?t=61648

Horizontal axis is most likely RPM

[Adrian D]

JoeTe, give us some feedback about your SOI changes:

https://mhhauto.com/Thread-SOI-with-...473#pid2213473

[RTB]

Seems worth looking into then.

Before touching anything here, seems EGT probe would be critical. It would also be important to fully understand the End Of Ignition calculation too.

The SOI map output can't be degrees as a range of 4 to 70 couldn't possibly be true. The duration output being the other half seems to have a fairly broad range too. Have you successfully calculated EOI?

I found a webpage that says more SOI produces more diesel clatter. I have definitely noticed more clatter since removing EGR when the engine is cold and RPM above 2000. Once warm, it goes away.

[Adrian D]

Maps might be in milliseconds, so they might need a factor applied:

https://www.ecuconnections.com/forum...6242&start=200

Earlier injector does produce more noise, as I remember from when my dad used to adjust timing on his Gold by rotating the injection pump

[RTB]

Now I re-look at the SOI maps. The area where the SOI seems too advanced begins around 2000 RPM. Right where I have noticed more noise...

Next time I drive it cold I might put my foot down a bit more. That should put the SOI on the other side of the lump, and clatter "should" reduce.

[JoeTe]

Originally Posted by Adrian D

JoeTe, give us some feedback about your SOI changes:

https://mhhauto.com/Thread-SOI-with-...473#pid2213473

I didnt try because SOI is dangerous so like I wasn't sure 100% prefer stay safe although i'm sure is not problematic but did a small research and create a trial SOI map but really I didnt found nothing really good info about SOI and EGR

[JoeTe]

Originally Posted by Adrian D

Maps might be in milliseconds, so they might need a factor applied:

https://www.ecuconnections.com/forum...6242&start=200

Earlier injector does produce more noise, as I remember from when my dad used to adjust timing on his Gold by rotating the injection pump

Yes I have my SOI map with factor applied to degress and max SOI is about 17 degress