Smoky D5

[Craig S]

I have an ex police D5 205 on a 60 Plate, and I have noticed that occasionally when I am overtaking, or am being generous with the big pedal that I can leave massive plumes of white smoke behind me.

The car has 130k on the clock, and there are no issues with the car, it accelerates smoothly, tick over is fine, no flat spots or anything else. The electronic oil level indicator is showing that all is ok with the oil level, and the dipstick is the same.

I have had diesels in the past which didnt have a DPF fitted which would leave a massive cloud of black sooty smoke behind me, but i thought the whole point of the DPF was to prevent these clouds of smoke.

Any thoughts?

[jrrose]

Sounds like the turbo Intercooler may be cracked if it is white. I would start there and get it checked. Happened to me on a previous D5 which was a known problem.

[Craig S]

If it was the intercooler which had a crack in it would it not be more of a constant smoke rather than just under heavy load?

Part of me thinks that it could be needing a decent blast on the motorway to do a full DPF regen, so over the weekend I am going to go and take it on a 40 mile 2500rpm drive down the motorway and see whats what

[D5meister]

couple of things to try

Take a look at the grille, if central low area is oily black mess - IC blown

You will get limp home sooner or later.


If all clean, could be the charge hose collapsing - a new air filter may resolve.

The original charge hoses used to collapse when oil softened them and u had a used filter.

They were swapped under warranty for one with ridges on the outside so they collapse less easily.

cud be split charge hose,

[Craig S]

I will get a chance to have a look over the weekend. Will run through all of your suggestions.

One thing i will add is that this only happens fairly high up the rev range (over the 3000 mark), but there is no noticeable drop in power when it happens. My friend who i asked to tail me, to check the colour of my red arrows display smoke, in their A3 will attest that i showed them a very smoky pair of heels and they couldnt keep up in the 30 to 70 sprint.

I think it is likely just a small hole in the IC or one of the charge hoses that needs full boost for it to have hany noticeable effect. But i feel it could soon develop into a much bigger issue.

I presume that with it being an Ex Plod car that any hoses that were due under warranty would have been changed as i cant imagine a misfiring plod d5 would have gone down well.

[Craig S]

I have had a chance to have a rummage in and around the intercooler and charge air hoses, and there are no cracks or holes that I have been able to identify.

However, I decided to take it for a long blast on the motorway, and sat for 15 minutes at 70mph in 5th gear, and another 20 minutes in 6th gear, and on my return journey, I gave it a bit of a boot in 2nd and 3rd gear, and all seemed to be well.

Is it possible that the DPF was starting to reach a point where it was needing re-generated, and the act of heavy acceleration was just dislodging some of the gunge in the filter?

I am also going to strip and clean the EGR valve see if that was perhaps contributing to the issue. but for now, I am going to place my investigations on hold til the issue develops or resurfaces.