Over Fuelling black smoke residue rear bumper

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Over Fuelling black smoke residue rear bumper

Postby Chippa » Thu Mar 14, 2019 1:57 pm


As the subject heading suggests, I have an issue where by I am having an issue with Over Fuelling, resulting in black smoke when accelerating hard or towing, which is resulting in residue of soot being deposited on the rear bumper. It is thick and very black after 100ks continuous travel. One minute it wasn't there and then bazzinga…. here it is....

Ive read the forums here, spoken to many experts and mechanics, had the EGR clean done, new MAF, new boost controller and a new HPD intercooler installed.

Background, serviced every 10 or 12000 k's at the most. 240000 on the clock now. Fuel usage gone from 8.0 / 100 to 9.0 / 100 (which is down from 10 after EGR clean. NO error codes. No new noises. No faults or issues when starting or towing … infact it is running beautifully except for the smokey residue issue and an increase of fuel usage.

So why my post, well I want to know two things, root cause and second, what additional harm can be done to the donk if I don't resolve the root cause asap.

All things considered it looks most likely a new set of injectors... before I go that route I want to make absolutely sure I have checked everything (even if there is technically no error code) … so if you've had the same issue I would greatly appreciate your advice.

Thanks inadvance

2006 ST-L TD Manual, MT MTZ's & Dueller D697 AT's, Pair of IPF 900's, 2" EFS lift kit, ARB delux front bar, Uniden UH500sx, 60 ltr on board water tank - pump and shower, 120A hr 2nd battery, Rear Shelf and custom storage draws.
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Re: Over Fuelling black smoke residue rear bumper

Postby DarekD » Wed Mar 20, 2019 10:14 pm

Chippa, the obvious one, any oil usage? Anything that old is on it's last legs, wheels. Not sure if anyone does engine boring and honing anymore. Can you buy oversize rings? Apparently, just googled it, $1200 for a kit. Plus labour! https://mrcylinderhead.com.au/product/n ... ee-postage
That only fixes the block. Once you do this the head will need work.
I would be getting low k 140kW motor from the wrecked one instead. They are just so much better than the earlier ones, and no DPF. I have one with auto and used to drive older D40 manual for work. Like night and day. Auto removes any turbo lag at gear changes.

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Re: Over Fuelling black smoke residue rear bumper

Postby Rob.M » Wed Mar 20, 2019 11:23 pm

I had a 206 model which had clocked up 200000 Km,when halfway thru a trip to Queensland (towing the van) the car started blowing grey smoke.By the time I got home the smoke was black,( the front of the van was covered in soot),so took it to a diesel mechanic who diagnosed it as worn injectors .They were replaced .No more smoke,engine a lot quieter and more power, all these symptoms crept up slowly so I hadn't notice them.
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Re: Over Fuelling black smoke residue rear bumper

Postby toymaz » Thu Mar 21, 2019 5:50 pm

Hi Chippa
If it is definitely over fuelling caused by injectors, its having a down effect on your engine. Have you happen to check the oil level because of it's seriously overfueling it won't all get burnt will wash pass the Rings and thin out the oil, causing more issues as well as high oil level.
2012 white St Auto, Safari Snorkel, 2"lift,. ARB bullbar ,egr block, 3"exhaust, provent 200,
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