E70 smooth running controller

[mxxxs]

Hi,
I have a ‘08 E70 3.0 sd.
Some time ago, I felt that the engine was running a little rough on idle speed in the morning for a few seconds and after a test with Ista D i got a smooth running controller error.
After testing the values, the cyl 2 was at about 5, over the limit.
I replaced the injector with a new one, but i still get the same error.
I measured the injector rates for about 20 minutes, and the values were above the limit only while the engine was on idle, and only when it was cold.
After 8-10 minutes of driving, all the values were normal.
Dies anyone know what might be the problem?

Thanks in advance
manos

[BevMW]

I would think that glow plugs could be a culprit, but they would throw an error code on INPA. They will cause it to run rougher for a couple of mins till it warms up.


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[mxxxs]

I replaced 2 of them about a year ago, and the controller also, but currently i don't get any error about them.

[ard]

Did you have an error related to the injector? or just a guess?

I forget, do those injectors need to be calibrated, or some other type of reset???

[pshovest]

I thought glow plugs shut off as soon as engine starts.

[mxxxs]

I did a smooth running test with ista d, and the quantity on 2nd cyl was above 5, while the max limit is 4.

[ard]

I recall using this test on an S62, I think it translated to 'run unrest'.

Turns out that it was due to a bad coil on the cylinder immediately BEFORE the one that was showing up as 'unrested' (so to speak)

Not sure what would cause that in a diesel.

[seattle]

Replacing injector does require adjustment. See here.

Note:
If injectors have been replaced, "injector characteristic map adjustment" must be performed:

Connect BMW diagnosis system
Identify vehicle
Select ”Function selection”
Select ”Service functions”
Select "Digital Diesel Electronics (DDE)"
Select "Injectors adjustment"
Select ”Test plan”
Start "Service" function with right arrow button.

[mxxxs]

Is this injector value visible while it is mounted or do i have to dismount it?
So to check if it is registered in the DDE.
Although I believe that it must be registered cause i replaced the injector to an authorized service center.

Thanks for the help

[pshovest]

I recall reading that the DDE executes an algorithm to improve running smoothness. It will make minute changes in injection quantities to individual cylinders to improve smoothness. This might explain why problem disappears when warm.