Technical Dpf over fuelling

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Technical Dpf over fuelling

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I've got a 2008 1.3 diesel 500, just wondering what other owners have done with the dpf.? Seems to me that the engine over fuels too much when it regenerates. I'm considering removing the filter and having remap but it's not legal for road use obviously. Anyone had any good succes at main dealers.?
 
I've got a 2008 1.3 diesel 500, just wondering what other owners have done with the dpf.? Seems to me that the engine over fuels too much when it regenerates. I'm considering removing the filter and having remap but it's not legal for road use obviously. Anyone had any good succes at main dealers.?



No direct experience with a Fiat 1.3 Diesel but had an Alfa 159 with the 1.9 Diesel engine. The whole idea is that it overfuels in order to burn clean the particulates in the filter. You'll fail the MOT if the tester spots a DPF missing, some go for a hollowed out filter or one with the internal gubbins pierced.
Main Dealers will not help you deviate from OEM spec but given your car is oldish there are a number of Indie tuning specialists: if you go for a remap, make sure they have Fiat/Alfa experience and don't just do a generic remap.
I had my Alfa remapped but did not have the DPF removed, unlike many I had no issues with it and always managed to regen OK. Later Fiat Diesels have the Euro 6 system which is less problematic. I read recently that all Diesels have software that makes them dirtier/cleaner depending on the air temp.....
 
When my 08 1.3 regenerates there's a lot of smoke out the rear. To the point the cars behind me back off.

I do a lot of miles so it regenerates once a week/fortnight.

I've a tune box hooked up so I put the black cloud down to it.

When it regenerates the instant consumption read out drops significantly, but only for the 20 or 30 secs it takes to complete.

Tom
 
When my 08 1.3 regenerates there's a lot of smoke out the rear. To the point the cars behind me back off.

I do a lot of miles so it regenerates once a week/fortnight.

I've a tune box hooked up so I put the black cloud down to it.

When it regenerates the instant consumption read out drops significantly, but only for the 20 or 30 secs it takes to complete.

Tom


Lot quicker than my 159, it used to take around 10-15 minutes and the consumption would plummet. The smoke is just the extra fuel burning off the particulates , the exhaust gets significantly hotter too, on mine if you stopped after a regen you could hear it ticking as it cooled down!
 
Lot quicker than my 159, it used to take around 10-15 minutes and the consumption would plummet. The smoke is just the extra fuel burning off the particulates , the exhaust gets significantly hotter too, on mine if you stopped after a regen you could hear it ticking as it cooled down!

Usually the smoke catches my eye in the rear mirror. If I'm on a busy urban road when it happens I lift off and try to 'save it up'. If I'm on a main road when it happens I drop a gear and gun it to try to burn it off asap.

I can just hear the other road users giving off thinking I'm about to break down not realising its a diesel 500 with dpf.

Tom
 
A DPF regen shouldn't cause visible smoke.
 
A DPF regen shouldn't cause visible smoke.

I'm sorry, I disagree. When my Fiat engined Saab 9-3 does a regen, on occasion, it can chuck out a big cloud of smoke as it burns off the ash before settling back down and becoming smoke free again. I spend up to 5 hours a day driving and I see this all the time as I've been behind enough diesel cars going through a regen to know what is happening. This is why I always have my car aircon on recirculation!
 
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A DPF regen shouldn't cause visible smoke.
You're absolutely right. It shouldn't. Reality is sometimes different though, especially when people find replacing a faulty DPF of a 5+ year old car too expensive.
 
I spend up to 5 hours a day driving and I see this all the time as I've been behind enough diesel cars going through a regen to know what is happening. This is why I always have my car aircon on recirculation!
Always on recirculation? 5 hours a day without fresh air? It would give me a headache!
 
Always on recirculation? 5 hours a day without fresh air? It would give me a headache!

Sorry, didn't make that quite clear, my work van doesn't have aircon, so I have to have the standard fan on recirc which does warrant the occasional crack open of the window.

My own car, well that's a different matter, I always have the climate control on recirc and never suffer from any head ache issues or sniffels, but then again, I have my aircon serviced annually on my own car.

But going back to topic, I still disagree about the smoke from regens. My car has only done 50k and I have the ability to check the DPF saturation levels which are fine by the way. It will kick out a cloud of smoke occasionally at the start of a regen. I think my car is Euro 5 standard.
 
Seems to me that the engine over fuels too much when it regenerates.
When my 08 1.3 regenerates there's a lot of smoke out the rear.

I've a tune box hooked up so I put the black cloud down to it.
You speak about overfueling. Well, basically that's exactly the working principle of a tuning box. It increases the injection quantities without the ECU knowing.

Maybe you should give it a try without tuning box, but probably things would only improve slightly. The box might have shortened the life of the DPF.
 
You speak about overfueling. Well, basically that's exactly the working principle of a tuning box. It increases the injection quantities without the ECU knowing.

Maybe you should give it a try without tuning box, but probably things would only improve slightly. The box might have shortened the life of the DPF.

Every now and again I disconnect the box for a few days. When it regens it still bellows smoke, maybe not quite to the same extent but not far off.

I also use fuel additives every month or so to help clean the system and I stay clear of cheap supermarket fuel.

I was under the impression the tune box increased fuel pressure, not necessarily adding more fuel. Maybe that's down to semantics.

I noticed a slight increase in mpg when using it, although I notice a bigger increase in mpg when I use my winter tires (175/60/14) compared to my summer tires (195/45/16).
 
I was under the impression the tune box increased fuel pressure, not necessarily adding more fuel. Maybe that's down to semantics.
Indeed tuning boxes for common rail diesel engines cause an increase of the fuel pressure, but with the same injection duration this results in more fuel being injected and therefore more power. But if you don't use the additional power, for example when driving at constant speed on a 70 mph road, then you have to lift your right foot a bit to compesate for the addional fuel that would be injected at the pedal position that you needed without tuning box.
 
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