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Discussion Starter #1
Hi Folks, new to this forum and still figuring out how to search for the correct information I need. So sorry if this question has been asked numerous times before. I have a 2008 159 1.9 Diesel, and this is the first diesel I have had which performs DPF regeneration, which I was completely oblivious to when I bought it (hindsight always seems to have 20/20 vision). I have read several post where people are asking how they can tell if regen is occurring. I wish I was one of these lucky people. I am left with no doubt whatsoever when my car starts a regen cycle, as it seems to put out more smoke and ash than an Icelandic volcano. Is this normal, the manual states you may experience a slight increase in smoke production. Either that is a severe understatement or something is most definitely wrong with my car. From what I can gather from posts everything else appears normal. It doesn't begin until needle hits 90oC on temp gauge, it last for about 10mins or 5-7miles. Sometimes it will happen after 200 miles the longest between regens was about 1000 miles (had long run up motorway during this time). During regen smoke heaviest on acceleration, smoke lightest if I keep revs around 2750-3000rpm (although I live in the countryside, the roads are quite twisty and keeping a constant speed isn't really possible). I have never had a warning light on in relation to DPF. Do you think DPF needs replaced or would flushing with a decarbonising agent help reduce visible smoke?

Sorry I posted this in the newbie section originally by accident, I will remove it if someone can tell me how to do that.
 
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I have a Toyota diesel, 2009 (apologies). It has dpf and regens.

What you describe, sounds very wrong, particularly the 10m duration and short interval between regen.

It could be a faulty (stuck open) EGR valve.
 

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I am also new to diesels and this regen thing, my 2.4 Brera is used mainly for long runs and generally the shortest run it gets will be 15 miles. When mine regens(I think) the reported MPG drops like falling masonary. I did about 2500 miles during September on fast French roads, I am sure it regened twice over that period. However, I cannot recall any excessive smoke generation or other emmissions, car felt a little less responsive and I guess it lasted for about 10 miles or so.
 

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It sounds like your car is doing a regen but there is no DPF or it has been gutted and is empty inside. When doing a regen you should not notice any smoke, it will sound different and the turbo gauge usually drops to 0 and the MPG fugue drops dramatically.

So maybe the last owner has the DPF gutted out as it was faulty but did not get the regen function removed, is my guess.

Rob
 

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Discussion Starter #6
Is DPF replacement a straight forward task?

Thanks for replies, it never occurred to me that someone might have already removed the DPF (I know the EGR is still in place and hasn't been blanked off, which is usually done by folks removing the DPF core, as I have had the EGR replaced a few months ago), I will try and get underneath and see if I can see or feel any tell tale signs of welding. I don't have an issue with having a working DPF on the car if it is relatively smokeless, but at moment I am paranoid about getting pulled over by police. If I get replacement DPF, is it as straight forward to fit as any other exhaust section, or does ECU need something done to it that would require it be replaced by dealer/approved servicing garage?
 

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Sounds Ok to me,

Regens lasting 10 mins sounds spot on,
Between 200 and 1000 miles spot on depending on how you drive, (a lot of around town will reduce the mileage between regens, lots of long motorway trips will increase it)

It does sound like your DPF has been drilled (Cored, or removed) if you are getting a lot of smoke.

But the police probably wont pull you over as they don't carry the equipment to do a smoke test at the road side, (so the most they could give you a pink slip to get it tested) and if they did have the equipment the fact that you had to stop and turn off your engine would stop the regen anyway so you would pass the test.

If your car is running Ok then don't worry about it.

Axe.

(I cored my DPF in my 1.9 and had the same symptoms until I had it mapped, although I don't know what your idea of a lot of smoke is, I could see clouds in my mirrors, and work collegues told me it was smokey never bothered me, passed MOTs with no issues)
 

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Discussion Starter #9
DPF now been replaced

Well done folks and thanks, you were correct about the DPF core being gutted. I bought a new DPF and fitted it this morning. The old one had been completely gutted (both the cat and the filter were gone). There were no obvious welds on the outer skin of the DPF so they must have used a long masonry drill from the ends.

Drove to work with no warning lights. I think it may have attempted a regen cycle when I hit the dual carriageway, but I got one puff of whitish/grey smoke then nothing visible in my mirrors. Will know for sure this evening on the way home. It may be coincidence, but I always found that regen was mostly likely after a long downhill descent where the engine is on overrun, but it may just be that my engine had just reached full operating temp by this stage in my journey.

Had also found the regens had been getting more regular of late. Taking differences in journey lengths and peoples driving styles out of the equation, is it the case that regens will happen more often as we move into Winter as the engine will use more fuel and produce more soot when starting from cold?
 
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