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Discussion Starter #1
Hi Alfistis.

I am the happy owner of a 2011 159 2.0 JTDM with 140.000 km on the clock. I bought the car at 122.000 km. In the time of my ownership, the PDF has regenerated 1 time (yellow sign showing up and information of not stopping the motor).

However, I "often" (may be once in a week or two) I experience the following:
Starting from home, driving my kids to school (4 km, 60-70 km/h).
Then heading to work. First 2 km with 50-60 km/h
After that, 4 km on motorway, 120 km/h.
Everything to now are normal. BUT THEN some days, when I leave the motorway, the power consumption stays high and only drops slowly when releasing the speeder. Normally when I release the speeder power consumption drops to less than 50 l/km almost immediately. But on these days, it wont drop of and the general power consumption is pretty high. Furthermore, the turbo pressure is very low, as if the turbo is generating almost no pressure. However, if I press the throttle and want to accelerate quickly, the turbo pressure rises quickly but drops very fast to no pressure (0 bar) when releasing the throttle. This goes on for about 10 minutes or 10-15 kmts depending on my speed. In this period the car cant keep it self running at idle in 1. and 2. gear. And after that, every thing works just normal/fine again. Sometimes I have recognized a smell of warm motor, but nothing critical.

So my question is: Anybody knowing whats happening? Is it a "initial" PDF regeneration or something else and hopefully normal thing?

Thanks :)

/Tom
 

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Hi Tom.

We are probably discussing the question in other topic already. Anyway I have a 2.0 with approximately 100.000 km on the clock. Almost always driving long distances (over 50 km in one trip) and have noticed very similar behavior.

Time to time the actual consumption is much higher at the same speeds / driving. Thought it is related to DPF regeneration however newer saw the orange light on. That could mean I never had this type of regeneration I assume.

Heaving the above in mind I believe it is not the DPF (which is a different design than on 2.4 / 1.9 and much closer to the engine itself) causing the problem. But the bloody EGR we are discussing here - http://www.alfaowner.com/Forum/alfa-159-brera-and-946-spider/412105-159-2-0-jtd-acceleration-issue.html.

My plan is to delete the EGR from the ECU by a specialist and drive for a while with DPF on. I believe the consumption will slightly decrease and most important the engine will run without those strange power decreasing modes.
 

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Sounds very much like a standard regeneration to me.... however i'd suspect an EGR fault at the same time, as it should be able to idle in 1st and 2nd gear (in fact it should hold the boost just off the stop when idling)

If you get a much boomier exhaust note when this problem is occuring, it's definitely a regen. I believe the regen light is only there if it's performing one out of unusual circumstances. (although I've yet to actually see a 159 with warning lights, rather than the more traditional MFD (multifunction display)
 

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Your issues sounds like a normal DPF regen.

The majority of the time you will NOT get a light showing the DPF regen is in progress (this seems to come on if the DPF is badly clogged and NEEDS to be done). Most of the time the car will cope with an interrupted regen (but will start the whole process on your next drive, which will cost you more in fuel).

Next time you experience this, try and keep driving until the turbo behaves normally, and the consumption returns to normal. This will reduce the number of times it happens, and also your fuel consumption.

On my 1.9 the whole process lasts almost exactly 10mins, and you only notice it looking at the turbo guage or fuel consumption, or should I say 'did', I've cored my DPF and got a dongle which stops it!

I'd echo the thought about the EGR, normally it shuts during regen, but if it is jammed open, it will be letting some fuel back into the manifold. Is your car slightly sluggish below 2,000rpm?
 

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Thanks for clarifying things about regen. I was expecting a warning light and never saw one.

Anyway what giblets is saying about the EGR is true. If it is stuck deleting from ECU won't help. Nevertheless if you are doing longer journeys 2.0 should be fine with DPF on. EGR is the pain in the ass in my opinion.

On the other side taking DPF out will help the performance. That is without question.
 

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Try cleaning it and fitting a blanking plate, can be bought, or made for under €5. Plenty of threads about it (and in the stickies.
If you fit a blanking plate with a hole, it will help, a fully blanked plate will bring up an error code unless you have a remap, or a dongle (€30).
 

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Discussion Starter #7
Hi.

Thanks a lot for the answers. Sounds like a normal regen.

To gilblet46...no, my car feels quite responsive from 1200-1300 rev and up. I had it re-mapped last year, so its not a standard software setup anymore. And to Moel; yes, my exhaust sounds more boomier and rattles sometimes when motor braking - only when the regen works.

Have a nice day,

:) Tom
 
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