Black smoke from diesel
 

I know its normal to get black smoke from a diesel but yesterday my 2.0tdci cmax 55 plate was blowing a hell of a lot out, cars behind were dropping well back and my tailgate is covered in crap. I did a round trip to Cardiff 300 miles and noticed under load it spewed it out in large quantities. Car has never had any engine faults before and has been serviced according to book specs. Recent oil/ air filter done 1200 miles ago. I did notice little bits of smoke before but thought it might have been because the dealer overfilled the oil.
Anyone got any ideas what may be the problem. Up to now Im thinking faulty injector or turbo seals but have no real idea.

black smoke is usually linked to too much fuel. I make a habit of nailing mine to the red line every week or so to clear it out

Doubt its turbo, thats normally blue smoke. Take it to a reputable local garage, they will be able to diagnose it better.

Nowt wrong with a cloud of smog, if its blue, watch out. My TDCi blows a lot of smoke, as others have said, let it warm up first them give it a bit of a rev and watch the crap blow out

The cardiff run is the third I,ve done in the last three weeks and I noticed the mpg drop from the usual 51-53 down to 48mpg. Performance still feels very strong but as I say the amount coming out is way beyond normal. The car has only done 52000 miles with full service history. Before the last oil change it barely gave out any smoke under acceleration.
I put in some diesel treatment in Hereford but that made no difference and I did give it some stick to the rev limiter.

Its usually white smoke for a blown turbo, Blue for burning oil and black for over fueling.

Could it be something to do with the particle filter either?

My guess is that there's a dickie sensor somewhere and its over fueling. If you get it on a Diagnostic PC it should show up any problems :).

Get a diagnostic test.

The lambda sensors could have gone, so could be worth checking those out and have a look to check see if they had already been replaced as there could be something else wrong down the line, they control the fuel mixture.

Carl

Could be a pipe split or come off, also cleaning the egr valve and inlet manifold might help.

Unplug the Mass air flow meter and see if it makes it any better, if it does, then you'll need to replace it. Im assuming if its a Pierburg and done more than 50k, then its knackered. If its a Bosch, then id be surprised if its gone below 100k.

The Mass air flow is a little box that sits on on the air intake between the filter and the manifold, also black in colour with a 6 or 7 pin connector going to it. Simply unplug (perfectly safe) and test the car out.

Failing that, you might have a faulty injector(s), if the spring has weakened then the effective duty cycle has been increased, thus allowing more fuel into the engine.

P.S, what mileage has she done?

Just had a quick look as its chucking down rain. The little box has siemans on it. Car has done 52000 miles. Will unplug it tomorrow. Its due its mot this week so will get it checked at same time. Im hoping that as it only blows out under load and not idle it will pass any emmisions test.
I dont usually drive with windows open but yesterday I did and noticed a noise like wind through tree,s every time I accelerated.

Not sure if they still do it but on diesel MOT they rev it to the limiter and check for particulates in the exhaust (my local garage had a disclaimer up saying that it was the persons responsibility to ensure the vehicle was well maintained so if it blew up they couldn't get sued or anything)

Sounds like a split Turbo pipe. Just remembered my Dads van had the same thing. :thumbsup:. It'll the pipe that goes from the turbo to the inlet manifold if it is.

Have you noticed a drop in performance?

Performance still feels strong but then I dont hammer it a lot. Its still got good mid range overtaking speed and pulls well in 6th gear but since I got the bike I save the looney stuff for that.

With the van the performance took a big hit but there again it was full of gear. Best let the garage have a look.

Black smoke is over fueling, you normally get this type of thing when donkeys fit the plug in boxes that trick the ECU instead of a professional remap.

EGR valve is normally puts on the engine warning light it recirculates exhaust gasses back into the combustion chamber to cool combustion and increase effeciency (MPG). If there is a problem and it goes ignored then uncooled gasses pass through the turbo causing it to overheat and wreck the turbo bearings.

If the light hasn't come on then I would assume it's a mechanical issue and not sensor related.

I watched a program not so long ago about second hand cars and they had a Ford Mondeo ST on it, it was a 2.0 TDCi and when they were going on about faults they mentioned that in some cases the injectors went at 60k. The other fault was all the rear suspension bushes fail at 40k.

I think you are going to have to pay a garage the stupid £30 for running a diagnostic check.

Check out this link but it doesn't sound like a cheap fix. :(:cry:

http://uk.answers.yahoo.com/question...3135828AAvL0wh

Doubt the diog will show anything. EGR is worth a try and check the hose for the turbo.

I've got the 1.8 version of yours and its never failed an MOT on emissions so wouldn't worry about it. If the engine light comes on then look at it :)

what eng size as it sounds like a pipe has split between turbo outlet to manifold can u hear a hissing noise on acceleration

I took it out this morning and unplugged the Mass air flow meter. Success no smoke trails behind me even under heavy acceleration through all the gears. Stopped after 3 miles plugged it back in and the smoke was back. Still got the air hissing sound so looks like the turbo pipe has also gone, will try to get it sorted this morning.
Many thanks guys for all the suggestions.

Try the pipe first, it might save you some money on the MAF

Even tho unplugging the MAF worked, it may very well have a split in the pipe, or a joint clip on the intercooler has blown off (very common). Check all of the pipes first with someone revving the car for air leaking. Failing that it's more than likely just the MAF has gone down.

Also, whilst your doing some auto diy, it's worth pulling the egr valve off and giving it a good clean. When those things clog up, it massively reduces performance. You'll see the difference afterwards.