Smoke when driving on high revs

Hi, I have owned German diesel cars in the past  Along with some  usual short drives i regularly drive a 250 mile round motorway trip once a week. This kept my cars driving cycles good and with regular maintenance i’ve never had any issues with them. As Auto clutch for my 3 series was dying after nearly 300k on the clock so i decided not to spend any further on it & picked one Toyota Verso 2010 D4D with 170k on it. Car looked clean, I test drove it, no smoke, starts and drives sweet so i take it home. I do a few short journeys as usual fir a few days without any issues but the day i take it to the work on a motorway i noticed huge cloud of smoke behind my car. As i never had this before i pulled out on next services , kept my engine running, no warning lights and then smoke disappears after a few minutes. I revved engine and nothing comes out. Thinking it could have been dpf trying to  regen i drove off again keeping an eye on it. Throughout rest of my journey i realised smoke coming out times and again (getting really thick at times, annoying cars behind me) and then dying off.  I thought might be a good idea to drive it with some higher revs as the car was not driven by previous owner for a few months (what he claimed).

Smoke thickness appears to be consistent with me keeping the lower gears (4th) keeping rpms to 2500 to maintain roughly 60 mph. This was getting thicker if car was driving uphill .  

If i put car on a higher gears e.g 6th , keeping rpms around  1500 and 70 mph, no issues at all or smoke but eml came on with vsc system check warning. Stopped the car at next services , checked code with my OBD it was P2002*Particulate trap efficiency below threshold*. I cleared the code drove off again. No eml again but smoke continued if i drive in higher revs.

Car pulls fine through each gear and i did not find any issues with the power or atleast didn’t get any indication that turbo was not functioning correctly.  

I am not sure if its DPF as after burning soot and cunk for nearly two hours i would have thought it would have cleared some of it. But P2002 code appears to be indicating towards DPF.

Just checking if someone can direct me into the right direction. I don’t want to spend replacing parts unless i know exactly what may be the cause but i would highly appreciate your input.

Ugh the DPF was one of the worst things they did to diesel engines...

I think yours is one that has a 5th injector to squirt diesel into the exhaust to burn all the soot off - A common problem in older ones is they get gucked up and instead of spraying a fine mist of diesel that immediately burns in the exhaust heat, it sprays a jet of liquid diesel which can't burn because it's not been atomized and just turns into air-show smoke.

Sometimes you can clean it by running several tanks of premium diesel, e.g. Shell V-Power Diesel, which has a lot of cleaning agents in it, or one of the many fuel system cleaner additives like Redex and BG244, until its spray pattern has been restored.

Otherwise it will need to either be removed and cleaned (e.g. by soaking it in brake cleaner to dissolve all the crud blocking the injection holes) or replaced.

Hopefully the DPF isn't also so blocked that it also needs to be removed and cleaned or replaced...!

Thanks Cyker,

Interesting to know about the 5th injector and what it could do on these engines, thanks for that. V Power appears to be a good idea so i will fill it up tomorrow as fuel is running low anyways. I am thinking of adding Wynn’s system cleaner as well hoping it clears out whatever it can. I will keep this thread open until hopefully i get to the bottom of this issue.

Out of curiosity is there any way of checking myself whether DPF is completely blocked ? I have no loss of power, no consistent EML, and consistent smoke (e.g none when idling or lower revs), ?

It's unlikely to be completely blocked if you're not noticing any loss of power; The system essentially measures air flow before and after the DPF to figure out if it needs to regen, which ODB tools can read, but you'd need to know what 'normal' is to make sense of the readings as there is naturally some normal drop due to having a big obstruction (i.e. the DPF) in the way.

Only other way would be to remove it but that's not an easy thing!

Without throwing loads of money at it, the easiest place to start is just running a few tanks of cleaner through and see if it improves. Most of everything after that starts to get more invasive and unless you're a dab hand a car DIY that means paying a garage...!

That 5th injector is difficult to get the cleaner to since it isn't always firing so may take a while to see any effects though... and this is assuming yours has the 5th injector (I'm just assuming it does as the whole plume of smoke out the back thing is a classic symptom of that existing and being blocked)