td4 excessive black smoke and rasp @ 2250rpm

Hi folks, new to the forum and seeking some assistance.

We recently inherited an 02 freelander Td4 S, chipped and very well maintained by my partners father for many years. Failed MOT on excessive smoke; we have gone through the usual fix attempts, new air filter, fuel system cleaner, PCV, oil & filter etc 'warming' the engine right before test but nothing has worked.

Engine black smokes (not a great deal but enough to fail) at low revs with a push of the throttle and then clears up at higher revs. Had it in for diagnostics at a diesel specialist who thinks it may be the injectors as everything else has come back fine. No compression test carried out.

Also very recently there seems to be a rasp or extra engine noise at 2250 rpm. It comes bang on 35 mph / 2250 rpm and then disappears as soon as speed rpm is increased. Note - car is on 174k. Any ideas guys? Any help would be very much appreciated.

biodesiel, parrafin desiel mix will stop black smoking. dont use to much parrafin as they will smell it.

Hi
Check for splits in the intercooler hoses especially 90 degrees elbow

Trev

Mass airflow sensor?

A rasping noise that can be cleared with a blip of throttle was what mine did before an injector went foobar.
If your engine chip is in a switchable box like a Ron box ...try turning it off as this will only make the injector fail quicker.

Hi All
I had exactly the same on my 2002 TD4 3 door, so struck a chord with me.

Clouds of Black smoke about 1800-2000 rpm or dependent on throttle position.
On light throttle it was less, but squeeze it too hard in a low gear - same result? Clouds of Black Stuff!

Did some research and looking at the threads here, and it looked like EGR or Intercooler hoses.
Mine has been chipped (TDI-Tuning) which has worked very well since day one.
So belt'n'braces - replaced EGR with a bypass (£39) New Blue Silicon Intercooler Hoses (set of Three for £89 from Gareth at DPH Hoses in Stoke - Highly Recommended by the way) PERFECT totally cured..... Runs like a dream and not a puff of the black stuff! Livelier, Crisper throttle, and I think better MPG, but too early to say?

From what I understand (and I am no mechanic) Black Smoke is too much Diesel - not enough Air... if one of the hoses that feeds the turbo or Intercooler has even the smallest of holes or splits it sucks in more air, the ECU then thinks it needs more Diesel and shoves it in...and on it goes until the unburnt diesel comes out the a**e end and Black Stuff...
2,250 rpm is about when the turbo boost peaks, (starts spinning up around 1,500rpm listen out for the whistle) I bet it is the same point as the smoke occurs - if chipped it may be lower.
Again exactly the same as mine.

May not be your problem admittedly, but well worth considering anyway.
(p.s. Passed MOT with flying colours, Emissons well below normal required)

Hope it helps, TD4 is a superb engine if looked after............
Cheers

Hi all,

thanks for all the advice! In particular jezzertd4, thorough, nice! Sounds like our situations are very alike.

Ours was chipped by Celtic and as far as I know has been spot on since installed. The EGR guts were removed at the same time, the hoses have been on for a while and I've checked them for splits but with the info that the smallest hole could have an effect I wonder about their efficiency. There are a few places where they have indents through at least the surface of the rubber, so new hoses might be a good idea.

Should the diagnostics have identified any leaks or should they have checked the hoses? We paid £60 for the diagnostics but apart from plugging it in i have no idea what else they did.

I have a new MAF sensor on the way, diagnostics identified it as failed but the engineer said it was unlikely to be the cause of the smoke due to it not occuring in the very low revs which chymes with your description jezzertd4.

I understand the same about the fuel air mix and it makes sense to me. With regards to the turbo; we can always hear it...I mean, quite loud. As soon as it kicks in which is quite low its a real whooshing noise that sometimes makes people look, which I find quite funny. I'm sure they expect to see a low slung chav mobile and not a hippo ripper with stinking muddy dogs in the back! Is it supposed to be that loud, you can tell its right behind the firewall at the drivers shin level without looking in the haynes! No need to listen out for a whistle. I don't have any noise level reference to go on, could this be a split hose to or from turbo, which could be adding to the problem?

Reading some of the info on here people have suggested, exhaust shield loose (checked-not it), cat breaking up, injector failing and engine seal damage accounting for the extra rasp at 2250rpm. All of which sound terrifying and expensive.

Were just trying to be cautious about chucking loads of money into it with such high mileage if there is further damage on the way...is there such a thing as a diesel engine health check? Thanks again and sorry for the essay!