Hi and thanks for the reply. I'm not technical at all so can't answer your questions fully sadly. What I can tell you is the car has done only 40k from new and hasn't had valve clearances checked to my knowledge. It seems to be running really nicely now and the exhaust smells a lot cleaner than prior to the EGR valve cleaning so that's done some good even if it hasn't cured the smoke problem. I've started and used the car a few more times today and there's been no noticeable smoke.

I've been reading about blue/white smoke problems in some diesels and believe that blocked breather tubes (?) can apparently cause similar issues with one sign being a build up of pressure which can be heard releasing when the dipstick or oil filler cap is removed. Is that true and could it be the cause of the problem I'm having? When would be the best time to check this? Immediately after a good run for example? A mate said a dirty/clogged air filter may also be the cause of smoke but I'd have no idea about that.

I'm due an oil/filter change so will get that done and see about additives such as those you recommend afterwards. In the meantime, I'd appreciate your further feedback on the above and any other advice forumites care to offer.

Many thanks.

Started car this morning and the problem is as it was before the EGR cleaning. On normal idle there is a very little white smoke but on revving a great deal more bellows out. After 1-2 minutes driving this disappears though.

@ Oldtoffee - Fuel filter hasn't been changed for a good few years again due to very low mileages. Same with air filter so must need doing. No idea if these could be relevant to the white smoke at startup issue though.

Thanks very much for the reply Peter. The smoking only lasts a couple of mins but I can't say I've noticed the car's been running any differently at those times. It's true, however, that she feels more responsive since the EGR clean and it certainly smells less 'oily/sooty/diesely' if that makes sense lol Yesterday the smoke was noticeable when first started up in the afternoon but I didn't drive anywhere at that point. I did a 15 mile start/stop round trip around town last night and ran fine all the way. Started her up 3 times in total and there was no visible smoke at all. In fact the problem seems to only be present on the first start of the day, especially if the car's not been used for a day or two which is quite common. I've started her up this morning about an hour ago and she jumped into life no problems and revved freely with no hesitation but was again smoking. The problem first appeared in the really cold/snowy weather around which time I also needed a new battery but I was hardly using the car then so didn't think too much of it initially as I thought it might just be condensation.

Hope this helps. :)

Just an update. The car's been running fine since I last posted but still smoking a bit on startup. It's still being used only a few times a week as usual although I did do a good high rev 40 mile motorway run as previously advised which doesn't seem to have affected the problem much.

Anyway, on Tuesday afternoon, it started up with not a trace of smoke! I immediately wondered if the fact that it had been parked in the sun (yes, remember that! lol) for hours that day was the reason. Since then it's been much colder again with some snow and yesterday when I fired her up for the first time since Tuedsay, the smoke was back. In fact she turned over normally on turning the key but suddenly cut out with a clunk before starting up easily on the second attempt. I'm still wondering if the outdoor temperature has something to do with the problem or could a dodgy glow plug be at the root of it? Any feedback gratefully received as always.

Edited by Mazda-Man on 05/04/2013 at 14:52

Thanks very much for the feedback Madf! Yes the dealer did a diagnostic and only said the injectors looked pretty good so that would tally with what you're saying. The car has now stalled twice when starting but the rest of the time it starts quickly and only sounds a little rough for a few seconds before it's nice and smooth.

Can you tell me if a leaky injector a big problem and is it likely to be improved or made worse by use of injector cleaner?

TVM.

Injector cleaning is likely to make things better - if at all. Not make worse.

It really need a diesel specialist to test the smoke (let the car cool down) and test teh injectors properly. Which means take out and test. Which means some cost.. I have no idea if the injectors are coded to the engine or not... If coded, it is possible they could only be replaced by a dealer with coding facilities.

Thanks very much for this. I think I'll give some cleaner a try first and see what happens as the weather warms up, if it ever does... lol

If the problem persists I'll probably contact the dealer to see what they'd charge to do as you suggest, purely as a reference point. They'll probably tell me the job requires special equipment etc. only they have so I'd like to seek advice from a diesel specialist too but don't know of any around this area - Bromley/SE London - so would be very grateful if anyone could point me in the direction of some.

TVM