[bmwPower99]

Check the below channel out. You'll have to auto translate to English
But it's worth it. Very informative.
They go over Egr cooler failures a fair bit. They mention in 1 vid that injector failures are more common on tuned cars. They show how this can burn and crack the top of the piston.
https://youtube.com/@H2MotorsGmbH?feature=shared

[bmwPower99]

Around 43 minutes they talk about poor tunes causing issue when too much torque is available at low rpm.

[Pepi]

Thank you very much for the link, but I’m curious, what is considered low RPM and too much torque?(I haven’t watched the video yet) Diesels are pretty low RPM running engines compared to their gasoline counterparts. As a tuned 328d owner about to upgrade to a stage 2 tune, you’ve got my attention, inquiring minds want to know 😉

[bmwPower99]

Originally Posted by Pepi

Thank you very much for the link, but I’m curious, what is considered low RPM and too much torque?(I haven’t watched the video yet) Diesels are pretty low RPM running engines compared to their gasoline counterparts. As a tuned 328d owner about to upgrade to a stage 2 tune, you’ve got my attention, inquiring minds want to know 😉

Good question! Unfortunately I have no idea. They don't elaborate in this specific video. You can check out another channel called darkside developments. They had issues when pushing these engines too much. I guess some tunes are too aggressive and the piston head is aluminium so it prob doesn't take much to melt them.

[TurboWeasel]

H2 Motors share some absolute golden nuggets of information

They teamed up with DITUPA and ARTEC Automobile on a couple of videos to discuss tuning and why engines fail with remaps, which was also a good insight.

They have other videos showing diesel injector nozzle failure which eats the piston crown away in a star fish pattern. Again, down to poor tuning.

The main takeaway from all of their engine failure videos is basically bad remaps turning off the component protection maps in the DME and just dialling everything up to the max.

Originally Posted by Pepi

Thank you very much for the link, but I’m curious, what is considered low RPM and too much torque?(I haven’t watched the video yet) Diesels are pretty low RPM running engines compared to their gasoline counterparts. As a tuned 328d owner about to upgrade to a stage 2 tune, you’ve got my attention, inquiring minds want to know ��

What they're essentially saying is shoving too much boost and fuel in too soon causes excessive cylinder pressures.

Modern small turbo gas engines suffer from a similar thing called LSPI (Low Speed Pre Ignition) from cramming too much boost in, too soon. OEMs already run these engines on the edge of knock, so you have to tread carefully with remaps otherwise pistons crack, rods bend and cylinder blocks buckle if you push things too hard.

Diesels are over built to handle that but essentially the same principal same applies, and they have their limits (especially the alloy block as it's not as thermally stable or rigid as an iron block), as they demonstrated in the video and why BMW go with a more linear boost map.

Another thing to consider is diesels have much higher pistons speeds than a gasoline engine. According to our friend Jason and his white board (Engineering Explained), at 3000 rpm, a diesel engine's piston speed is 12m/s. A gasoline engine wont see that same piston speed until 4500rpm.

So piston speeds and cylinder pressures need to be tightly governed to avoid damage.

In other words, leave it standard or 'series production' in German

Another takeaway from most of their videos is the customers getting engine rebuilds ask for the standard software to be flashed back on

If you really must get a remap, BMW's own MPPK is probably the safest bet in terms of longevity.