Smoke Screen

[mcandmar]

It all started after a hard launch and just after shifting into 2nd the engine had a big stumble, all i could see in the rear view mirror was a wall of smoke. Weird thing is after pulling over and checking it all out it recovered and drove fine again, no visible signs of smoke out the exhaust, it all seemed fine.

Then this morning i started it up and drove off down the road and it didn’t feel right, smoke trail out the exhaust was visible again and it ran pretty crappy. Came home and had a good poke around again but still can’t put my finger on the problem. Oil pressure and temps havent changed.

Anybody got any ideas? It seems to run fine after everything has fully warmed up, cold starts seem to exaggerate the problem

[Knight Rider S4]

What was the water level like?

[quattro]

Look at your cambelt has the tensioner pulley started to give way, that sounds like mine last week. if you have asudden big loss of power turn you engine off! i did at 100mph and my engine is ok now!

[mcandmar]

Waters fine, and from the smell i'm pretty sure its oil burning causing the smoke. Strage thing is its not a constant problem, sometimes it goes away and drives fine.

A friend suggested i might have broken a piston oil ring. I'm not sure what effect a broken ring would usually have

[Briggsy]

oil breather PCV??

[valjo]

oil breather PCV??

yes or blocked engine breather lines....

[mcandmar]

Had a look around the crank case breather plumbing and it all looks fine, no blockages or leaks. I tried to pull the spark plugs out and have a look but i couldnt get the plug leads off. Upper part is free as i can twist them around a bit, but the part on the plug will not budge

Seems to be getting better, and once its fully warmed i cant tell the difference. It is using a bit of oil but i'll keep driving it and see what happens.

[Ghiest RS2]

What was the final problem or solution? Having the same thing, and now its progressed to a rough idle and running rich. No pressure leaks, or at least that's what the shop says.

[mcandmar]

Never did get to the bottom of it, oil usage has gone back to normal but it’s still lumpy on cold starts.

I have a theory that’s its something to do with the valve guides. If i drive it very hard and get it fully warmed up, then come back the next day it blows a cloud of white smoke and struggles for the first few seconds. Seems to me like oil is leaking past the guides and sitting in the cyl. For everyday driving its fine, only when i push it hard it does that.

Doesn’t explain the first issue, that was like somebody poured a load of oil into the intake manifold, hasent done it since then

[220bhp]

Could be a build up of oil in the turbo pipes or intercooler getting burnt of when you push it hard.

[mcandmar]

None turbo mate