Hi all, I was following my wife the other day while she was driving our Panda Cross. At certain times it was blowing some black smoke out, usually accellarating which although it was'nt a great amount but still a little concerning as it has only done about 18000 miles. It is going in for it's 3rd year service next week so I was wondering if I need to point this out to the dealers?. Bearing in mind it still starts and runs very well

basically that'll be unburnt fuel,
so usually either trying to pull a high gear at low revs will do this momentarily,
or a choked air-filter,
with your service due this COULD be a possibility,
Charlie

I've a 2 wheel drive MJ which doesn't have a diesel particulate filter (DPF) and I assume the Cross also doesn't have a PDF. (readers please advise)

I drive my MJ very economically and it doesn't smoke, but I do open it up once a week, full throttle and 4,000 rpm, and sometimes it smokes like a bonfire of green wood.
However it does clear after 5 or 10 seconds, and I believe it does clear the combustion chambers or turbo or manifold or exhaust or somewhere of some carbon that was laid down. It also exercises the turbo wastegate.

Give it some stick, an Italian tune up, and if it smokes afterwards in normal driving then I would think there may be something wrong with it, but a bit (or lot) of smoke on initial thrashing is OK

Thanks for replies, hopefully new air filter etc will cure this after service tomorrow. It does do regular motorway runs for about 20mins morning then after work. will re post in a week or so to see if there is an improvement.

Hi,
I'm a new Cross owner (i.e. I'm new, the Cross isn't!) and have also been a little concerned by occasional black smoke. My local garage (not the seller of the vehicle) tell me it's nothing to worry about.
Did your filter change make a difference? Has the new filter got a black foam strip along it, attached to the paper fins, or is just paper alone?
Cheers.

you only worry with an oil burner when it doesn't smoke occasionally .

Dont sweat it,

Hi there,It did seem better after the service and the air filter did have an orange foam strip going around it. Just checked it to make sure they had done it.

Turbo diesels can suffer a bit of smoke if the air/fuel ratio is imbalanced.

You can easily imbalance it via the throttle pedal, you signal for more speed, so it adds fuel, but it takes a moment for the air/turbo to catch up, which is why they'll always puff a little when you clog the pedal.

It's chicken and egg, you need more speed, so it needs more fuel and air, there's little control over the air entering the engine on a diesel, so fuel is added to make the engine speed increase and drag/push more air in.

A dodge MAF can cause issue, whether it's dirty or broken.
The air is measured on the way in before the turbo via the MAF (Mass Air Flow meter) but after the air filter and the fueling worked out and added (injectors) depending on other sensor readings, throttle position, temp etc.
So effectively a dirty air filter would limit performance as it would limit the fueling to the air it measures.

Air leaking out after the MAF via a split hose is another common one, often a hiss or a fart sound can be heard when under load.
The air is measured, fueling worked out, but some of the air has gone missing!

Wonky injectors with poor spray pattern can over inject or dribble.
Usually noticed at cold start with lots of unburnt fuel appearing white in the exhaust.

Prime suspect though would be the EGR, a headache of a device that most diesel onwers dread. Under certain conditions is meant to introduce exhaust gases back into the air intake to lower combustion temps (and Nitrogen Oxide)

On a steady cruise or over run, fuel injection is limited or stopped altogether but air it still pumped in (as mentioned, there is no control over air), this leads to higher combustion temps and production of the green house gas Nitrogen Oxide.
The EGR should open at these points and allow exhaust gas which lacks oxygen back into the air intake/cylinders, which will lower the temp of combustion.

I theory, it's great, in practise it's a friggin headache.
Soot (from the exhaust) and oil (from the crankcase breather that is plumbed into the air intake) combine in the valve to produce the nastiest substance known to man, this bungs it up to restrict air flow or jam it up so it fails altoghter and sticks open.

This is one off a Jag being cleaned, believe it or not, it's actually pretty clean to start with, they get much worse!
http://www.jaguarforum.co.uk/f26/egr-removal-cleaned-photos-36133.html

One tiny correction. A leak after MAF will suck extra air in and get you a lean mixture.

gr J

A3jeroen said:

One tiny correction. A leak after MAF will suck extra air in and get you a lean mixture.

gr J

Click to expand...

Yes, I should have written turbo, hence the hissing and farting noise.
Thanks mate.

You're right. A leak after the turbo (or a hole in the intercooler) will blow and cost you lots of power.
Conclusion: We don't want airleaks anywhere

gr J