Smoke on overrun

[Frosty]

As the title suggests really, my estate seems to have a bit of white/blueish smoke come from the exhaust on the over run. I had noticed it but had a mate following me back along said about it. It drives and pulls ok and no sign of the white/blueish smoke when pulling on, other than i have noticed it when i reverse reasonably quick. Anyone got any issue to what the issue could be all?

[JTaylor2005]

Whitish smoke could be unburnt diesel? Maybe a slightly leaking injector not closing properly? Could that be possible?

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Or possibly a leaking valve seal or turbo seal?

[Poodle]

Sounds like your turbo is dying to me. You don't tend to see valve stem seals go on these, but i guess it's still a possibility.

[Frosty]

Whitish smoke could be unburnt diesel? Maybe a slightly leaking injector not closing properly? Could that be possible?

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Or possibly a leaking valve seal or turbo seal?

Hmm yeah not sure, pretty certain it wouldn't be injector relate as i fitted some back along and had them tested beforehand.

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Sounds like your turbo is dying to me. You don't tend to see valve stem seals go on these, but i guess it's still a possibility.

Im wanting to say its not turbo related but not sure, it seems to boost like it always has done. Also i had the turbo off back in the summer when i had my boost leak sound that i thought could've been the turbo but was the inlet gasket in the end, and the turbo felt all good. No more play than you would expect from it. The only other thing that could be linked to my issue is when you rev it up on the spot it chucks a bit of smoke out and sounds like a bit of a misfire. It also done this before i changed the injectors.

[Poodle]

Sounds a lot like it's drinking a bit of oil tbh, that or you're low on compression on one cylinder. Do a comp test next time you get a spare minute at work.

[Frosty]

Hmm, i wouldn't say it uses really much oil at all. I may have to top it up in between services about 1/2 litre max and i service it about every 5000 miles. I will see what i can sort out. Ill try and get a video if poss.

[Ruan]

Check that your breather isn't blocked or the pipe isn't kinked.

That's a classic time for it to show up, when you lift off and it'll blow a cloud. Remember to check the one way valve in the rocker cover, if that's blocked, I'd put money on it showing up like this.

[JTaylor2005]

Out of curiosity what is the one way valve for in it? The breather only goes into the before turbo intake so it should never be pressurised?

[Frosty]

I checked it back along when i took the rocker cover off to replace the seal and gave it a clean out. I've just got a pipe on it that goes to underneath the engine.

[Ruan]

What bore is the pipe...? Remember that these normally have a vacuum on the crankcase - if for some reason the engine is breathing heavier than normal, that will almost certainly be causing blowby under light load conditions...

[Frosty]

What bore is the pipe...? Remember that these normally have a vacuum on the crankcase - if for some reason the engine is breathing heavier than normal, that will almost certainly be causing blowby under light load conditions...

Ah umm think the pipe is like 20mm. Its whatever goes straight onto the tube on the rocker cover. So it's nothing really to worry about?

This wouldn't cause the kind of misfire when its revved up on the spot though would it? I'll try and get a video of it.

[JTaylor2005]

Having a vacuum on the crank side of the pistons helps seal piston rings as well. So maybe they are passing oil slightly?

[Ruan]

Ah no, didn't know it slightly missed when revved... Did it do the slight miss when revved before the injectors were changed?

[Frosty]

Ah no, didn't know it slightly missed when revved... Did it do the slight miss when revved before the injectors were changed?

Yeah did it before I changed the injectors, was hoping that was the issue. It's fine when driving though.

[pug306driver]

So the round part of the cam cover by the battery end has a one way valve?

Is there room for a worm drive clip at the starter motor end of the large diameter breather rubber pipe, looks rather cramped down there ?