Black Smoke on hard accelleration or under load

[rovertone]

Went to my first Midlands Nano meet yesterday (Thanks Arctic) and took opportunity of a T4 health check.

All was well the only exception was an electrical fault that wouldn't clear on the EGR, so next week I will investigate and firstly disconnect it and see if there is any improvement.
Other than that I will look again for any air leaks between turbo and inlet manifold, all looks very clean and dry around intercooler connections, as said before top i/c hose looks sound but is very pliable so probably worth changing to rule out any problem there.

MOT isn't till March so have some time but with another trip to Portugal planned for September it would be good to solve problem soonest to see if mpg can be improved.
Thanks for all input, will post any eventual outcome.
Tony

[Avulon]

over 2 pages of thread and I'm amazed no-one has written...




No Smoke, No Poke!

[Number 6]

Originally Posted by Avulon

over 2 pages of thread and I'm amazed no-one has written...




No Smoke, No Poke!

To be honest There is Smoke and there is smoke IE screen

[grivas]

Originally Posted by RogerHeinz57

Most of the diesels smoke a some stage of accelerating, makes little if any changes if you run it on Shell or other proper fuels against cheap supermarket fuel. The power upgrade will make more smoke due to elevated fuel pressures and greater amounts of fuel injected, and as you clearly have done most of the obvious fixes, there is one that not many have spoken about.
It is not uncommon for the turbo seals to allow a small amount of oil through to the lower hose attached to the intercooler, this is again quite normal and no real problems to the car, but the long term effect is this.....
The intercooler has a small puddle of oil at the bottom, when the charge is generated by the turbo unit, it enters the intercooler, whips up a nice oil contaminated mist collectively with the hot gasses and then is introduced into the inlet tract and then off it goes into the engine and becomes burnt causing noticeable smoke.
This is worsened by the fact that the intercooler internals are heavily coated in oil from many years of punishment of hot gasses and oil mist. The efficiency of the cooler is marred and the engine fueling will be right but the gasses will contaminate everything it travels through ! On my car which has the 160 and also a synergy 2a on mid settings smokes fairly well under heavy load usage, the plan is to remove the intercooler and clean out with brake cleaner thoroughly, This will enable fresh intake gasses cooled properly.

Sorry for the long winded reply, but you did ask for info !

Should the smoke then be more blue than black if the engine is burning a little oil? or am I looking at it wronngly?

[Avulon]

Originally Posted by grivas

Should the smoke then be more blue than black if the engine is burning a little oil? or am I looking at it wronngly?

It'll be black - the oil in the intercooler is most likely as black as pitch already with soot contamination (as is the oil in most diesels just a few miles after and oil change).

[rovertone]

Originally Posted by rovertone

Went to my first Midlands Nano meet yesterday (Thanks Arctic) and took opportunity of a T4 health check.

All was well the only exception was an electrical fault that wouldn't clear on the EGR, so next week I will investigate and firstly disconnect it and see if there is any improvement.
Other than that I will look again for any air leaks between turbo and inlet manifold, all looks very clean and dry around intercooler connections, as said before top i/c hose looks sound but is very pliable so probably worth changing to rule out any problem there.

MOT isn't till March so have some time but with another trip to Portugal planned for September it would be good to solve problem soonest to see if mpg can be improved.
Thanks for all input, will post any eventual outcome.
Tony

Update
I have disconnected the EGR via blocking off the vacuum and disconnecting the plug from the vacuum solenoid.
Unless its my imagination pick up seems much more crisp even when revving from idle but I still have a smoke screen under hard acceleration, I'm taking the caravan out next week so will see how that goes.
So looks like I need to start investigating intercooler and maybe change the soft (original) hose although the hose and all around the intercooler connections are really clean.
The EGR valve does put a bit of a blockage into the airflow so I am thinking a bypass might be beneficial for air volume with 160 remap?
I'll keep on trying!

[Avulon]

One thing I haven't seen is mention of the airfilter quality or condition. This is by far the largest blockage to air flow in the whole system. A clean air filter is a must.


Now to address the below...

Originally Posted by rustymotor

Hi Chris,

To my mind diesel is an oil and as such a lubricant cleaner is cleaner as such may remove lubricants again, will bow to superior knowledge..

Diesel is an oil and a lubricant .


Cleaner is cleaner? may remove lubricants... or may not - especially if it's an oil.... Not all cleaning fluids are the same, There are a huge variety of cleaners - just for injectors, here is some reading for you... link

Most injector cleaners contain (unsurpisingly) solvents - many of which are carried in an oil derived base....

[rovertone]

Thanks, air cleaner is good.
It was suggested that I remove the outer 'cotton wool' to give better airflow. Whilst it may be worth a try I don't think it will sort the issue, the more I think about it an EGR bypass will open up the air duct.

[MissMoppet]

To clean the injectors give it an Italian tune-up. 3rd gear, foot-down for 5 miles. Certainly worked for me. Smoke gone on acceleration thereafter.

[Nantwich 75]

Put one of those additives for cleaning injectors into your fuel tank.