Rough idle, stalls sometimes and smoke from exhaust

Hi guys, first of all sorry for my english as it's not my native language.

I have run into a problem with my 2004 Accord 2.2 i-CTDI.

I use it on longer journeys to get to work. (100 miles a day return). There was no problem until last Friday. Car started with rough idle and some white (maybe a bit blueish) smoke from the exhaus. Then it stalled. After 30 seconds on more than 3000 RPM the symptoms are gone after tons of black smoke came out from the exhaust. Then I was able to drive it home with no problems, no smoke.. Next day the same problem in morning. Light smoke from the exhaust and rough idle. After 1-2 minutes on high RPM some black smoke again, but not as much as the day before. Then it works like a charm again until the next morning.

Nothing came up on the dashboard and there are no fault codes.

Mobile mechanic said he would try a new fuel filter. I am planning to get it to a mechanic for a full inspection and servicing but now I need the car daily to get to work.

Any ideas would be really appreciated!

Cheers,
Mark

Possibly a leaking egr valve or bad injector. Needs a proper diagnostic really

Thanks for the answer. Now the sytmptoms have been changed a bit.

The car had a full service 2 weeks ago. New fluids, filters etc.

The car starts even in cold mornings and does not stall. But the engine is really weak until it warms up. Car doesn't want to accelerate even on flat roads. Need high RPMs to get some power. After 4-5 miles of driving the engine gets warm enough and it has the power again. If I leave the car at work for 8-9 hours it needs to warm up again to have the power.

Huge amount of black smoke is coming out from the exhaust when I hardly accelerate (after let the engine warm up)

Two mechanics said they couldn't find any problems. Im planning to go to a diesel specialist but the first free slot will be 3 weeks later.

Any ideas would be really appreciated.

Thanks in advance!

What kind of mechanics are these? Should be easy to identify the problem even with some basic diagnostics.

Can you book it in wth me?