Fuel system work - RPM Drop

[mikkhh]

Not related to your problem, but since the topic of egr tuneup came up.

Keep a close eye on dpf differential pressure readings. Aftertreatment Control Modules located on the cans go bad on them quite often, first symptom is diff pressure faults. After that usually diff pressure sensor is replaced (or somebody decides to "deman" the thing and then not long after acm itself dies, but that "deman" is joke which requires acm to be connected, unlike the EURO3 conversion which is meant for high sulphur diesel countries), also wiring, then dpf itself. And still faults no fix no avail, until there are no communications with acm module.

Also egr coolers do crack on them and cause leaks into engine, again just a thing to keep in mind when you have a coolant loss, on those I would not start from oil pan pressurizing when looking for internal coolant loss.

Spun bearings wise DD13 15 engines have hard material two metal bearings (aluminium-steel), lots of others have tri metal (lead/babitt - copper - steel), that wear quicker, but are more forgiving for dry starts etc. Same exact story is on Mercedes cars, since DD is owned by daimler since 2000s lots of design things carried over, mercedes cars also have bearings that are very hard and do spin, even mains. Just doing long life oil change intervals and having abrasive soot form up in oil galleys can spun mains on benz cars, does not take much. I have measured crank runout on ones that got locked up after couple minutes of idling, all checked out fine.

I have also heard about plastic oil pickup tubes cracking (where it is ultrasonically welded together) on DD13 and DD15, therefore creating catastrophic damage.