E70 smooth running - injectior problem?

[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.
Does anyone know what might be the problem?

Thanks in advance
manos

[Chrispy]

Are we talking really cold starts?  If we're into around zero degrees and below overnight mine is lumpy on start for a few seconds but sorts itself out fairly quickly, and I have a fault code on the glow plug module.  I take it you have no codes for that unit along side the existing ones?

[NehalX5]

Would a reasonably lumpy morning/cold start signal glow plug module issues? Although, we haven't had any codes thrown yet.

[Chrispy]

I can only speak from my own recent personal experience. Since getting the car, on cold mornings the starts were always a little lumpy. We're talking approaching zero degrees. After say 5 or 6 seconds it would smooth out. A recent trip to a dealer for other works revealed a fault code for the glow plug control module, which made sense based on what I was seeing.

I'm not saying that's the cause of your issues but a lumpy start when cold on diesels "could" be glow plug related. Less so with modern ones as the injection pressures are so much higher now.

I'd have thought if you had injector issues they'd be present at all times, or at least other symptoms too like loss of power, poorer mpg, etc.

[Marrow]

Mine does the same on cold starts (low to zero temps) but no codes and fine after 10seconds tops ?