There have been quite a number of articles over the years evidencing folks' wariness about this issue. As we are all now either locked in our houses or at best driving short distances to vital suppliers, I expect the topic to arise again in a few weeks' time. I have noticed occasional, very brief hesitation from my 2014 X-Trail (old shape) when first started on colder mornings. Maybe it's nothing, and frankly to be expected; but maybe, I wondered, it could be the beginnings of something untoward. And as always, one's mind leaps to a bad conclusion and starts to justify why that is the right one!

I have seen advice to drive for 30 miles using 4th gear at 60mph or more. I have seen possibly contradictory advice that it is the use of higher revs which produce more sooty exhaust, thus making the problem worse. I have also seen advice that a good, long run in top gear at 70mph is what is best to regenerate the filter.

Perhaps these more modern engines are better at keeping themselves clean? At the risk of incurring moderators' ire, could we look at the issue again?

I have the earlier 2008 T31. It drives perfectly, no hesitation or other poor performance issues, but it does have a tendency to put on its DPF light a little too frequently for my liking. Provided I catch it quick enough, i.e. before the EML comes on as well, a 30 minute drive at a constant speed at over 2000 rpm usually does the trick. However, I have read on another thread that the later T31s had an ECU software upgrade, and the problem I have doesn't seem to be prevalent on them. When I can go out again I'm going to look into whether I can have mine upgraded to the later software. It's the same engine so there should be no problem.

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I have the earlier 2008 T31. It drives perfectly, no hesitation or other poor performance issues, but it does have a tendency to put on its DPF light a little too frequently for my liking. Provided I catch it quick enough, i.e. before the EML comes on as well, a 30 minute drive at a constant speed at over 2000 rpm usually does the trick. However, I have read on another thread that the later T31s had an ECU software upgrade, and the problem I have doesn't seem to be prevalent on them. When I can go out again I'm going to look into whether I can have mine upgraded to the later software. It's the same engine so there should be no problem.[/quote]

Thanks for this reassurance; it sounds like it's the electronics shouting, "WOLF", more than actual impairment of driving. Still ...there have been no warning lights on my dashboard and I'd like to keep it that way.

Hi,
Have you tried a DPF cleaner. I use Hydra which is under £10 (others are available). You can buy it on Ebay. Works great and cleans DPF and associated bits in the engine and exhaust. My car runs better after I use it. Worth a go.

Ooh! Thank you, Fox Xtrail I might see if I can get hold of some.

Yes I've tried DPF cleaner and it's difficult to say whether it made any difference at all, as the light still came on again. Whether it would have come on sooner if I hadn't used it is impossible to say. I must admit I am very sceptical about these "wonder cures" that you pour into your tank, just as I am sceptical about the so-called "super-fuels" that cost way more than "ordinary" branded fuels, or even supermarket fuels. Especially after trying a tankful of super-diesel in my Volvo and finding that it ran no better and even gave slightly worse MPG than my usual Sainsburys diesel. Having said that, I haven't used supermarket fuel in my X Trail, just in case as it has a DPF which the Volvo didn't. But I still wonder if I'm throwing money away.

If it's any consolation I have a 2011 facelift Tekna and have never had the light come on (it does work) and never had any DPF issues. Mine is the updated engine with the latest software and occasionally I too get a slight blip either from just cold or when I have been in heavy town traffic and it's warm. As soon as I am out on open road it disappears. Mine is now on 176k miles and engine is quiet and sweet as a nut (touch wood). I've had it since early Dec 2018 and loved it. I did run an additive called 345 or something to have an effect and I do get excellent mpg. I always use top notch oil as well and have changed gearbox, transfer box and diff oils. To my amazement at 165k the oils that came out of these were all in excellent condition so either the previous owner also did it but didn't document it or Nissan did well! Mine is now tuned by Celtic with 221hp and is wonderful.

Wow! The engine must have been in decent nick for the tuning company to agree to go ahead with such a serious increase in power. Did the torque figure go up too?

I have since spoken with my son (an automotive engineer who works for a consultancy which is hired by OEMs to fix design problems). He reckons that the ECU will be programmed to trigger a DPF burn under certain conditions - usually when the engine has run at more or less steady speed in highway driving for a little while - and will dump extra fuel into the mixture to burn off the offending residue. This is why driving in lower gears at high revs doesn't do the job. His guesstimate of the time required was between 5 and 10 minutes. But he is talking theory here as he isn't familiar with the performance set up of the X-Trail engines.

I can report that 20 minutes of 60mph to 70mph driving dispelled the engine's hesitation at start-up the next morning. Perhaps that's the answer? Either way, he confirms that everyone should make sure they do similarly at the first signs of such behaviour, since having the garage deal with the issue of a fully jammed up component (i) will cost a bit and (ii) may not clear out all the coating from the pipework.

Thanks everyone for your input! I look forward to being experienced enough with my X-Trail to offer quality 'real-life' advice to you all

Torque went up quite a bit as per...................... https://www.celtictuning.co.uk/services ... t3-content

The agent did a comprehensive check on the car before it was hooked up to computer which uploaded existing software to Celtic who then within about 20 mins downloaded their re-map to my car via his laptop. IIRC it took about 45 mins in total and totally transformed the car. It was never going to be a traffic light racer but once on the move - boy does it go. Greta when in a hurry off a roundabout on wet road surface ans simply hit loud pedal and let the 4 wheel drive sort itself out and give grip when needed and it feels totally palnted while 2 wheel drive scrabble to keep up :) Seriously though mpg has improved to upper 40's as normal and no need to change gear as often to overtake/get a move on.

Cripes! That's stunning. BMW X-5s, eat your hearts out...