Is it turbo time or something else - piston rings?

[karlbar2k]

pulled up at traffic lights and noticed that the car is smoking when sat there,  then give it a rev, puff of smoke then smoke clears, sat at the traffic lights for another minute all OK?  so effectively engine is on overrun then idle with smoke, rev it big cloud then idles OK and pulls away with no further smoking?  Piston rings maybe?

 

 

[Liverpool-Lad]

Not due to the weather is it, or something more sinister?

[karlbar2k]

I know the turbo is a bit long in the tooth and is going to need replacing soon but hoping I can old off till after crimbo.  Not sure if its oil getting to the exhaust via some route other than the turbo though

[Saints92]

What colour is the smoke?

[VrsMule]

Mine does that, white smoke. Oil and coolant levels are spot on. I noticed the water temp gauge fluctuating between 70 and 90. Mine is intermittent as it hasn't done it for a while but some days it's like a steam train !

[VrsMule]

Suspect cause is the water temperature sensor.

[petrolbloke]

As above, what colour is the smoke?

[David 8]

Valve stem seals aren't great on the 1.8t

[karlbar2k]

hey David, thats what I was worrying about just had stainless system fitted £££ and first thing that happens after a couple of days is big plume of smoke at the lights :p  Missing Cardiff a bit now that I'm all the way up here in Yorkshire.  you still running a Mk1 VRS? cant believe I am 10+ yrs with the skip  on 183K now and pulls great when the turbo decides its going to boost.

Edited 20 November, 2016 by karlbar2k

[David 8]

What colour smoke is it? Could just be condensation, I think my VS seals were gone and it coughed out blue smaoke on the overrun.

 

Mines long gone now, got rid in March 2013, now rocking a white 123D, first and last diesel, I miss 7k RPM, how come your oop north these days ??

[KenONeill]

As others, telling us what colour the smoke is will help lots with diagnosis!

[karlbar2k]

its blueish tint so I know its oil just not sure where from.  

 

I moved oop north so the missus could be closer to family and my daughter moved up this way too 6 months after so we're taking over

 

if the oct fails the MOT tomorrow you can have first dibs :P  

[KenONeill]

OK, likeliest suspects are piston rings or valve stem oil seals, so do dry and wet compression tests (if compression rises on the wet test the problem is rings).

[bigjohn]

OK, likeliest suspects are piston rings or valve stem oil seals, so do dry and wet compression tests (if compression rises on the wet test the problem is rings).

 

 

Oil compression test good but be aware compression will always rise a bit in any circumstance - it's if it make a big temporary difference then the problem is piston/rings

 

However - smoke after overrun - sounds like stem oil seals 

Edited 28 November, 2016 by bigjohn

[karlbar2k]

doesnt always happen either?  can go days without seeing any then big cloud of smoke at the lights. Then nothing again?  can a blocked PCV system cause similar as its been about 80k since I cleaned the valve and changed the pipes

[bigjohn]

doesnt always happen either?  can go days without seeing any then big cloud of smoke at the lights. Then nothing again?  can a blocked PCV system cause similar as its been about 80k since I cleaned the valve and changed the pipes

 

Yes, a blocked PCV will cause the engine to pressurise which can blow oil past valve oil seals

[KenONeill]

doesnt always happen either?  can go days without seeing any then big cloud of smoke at the lights. Then nothing again?  can a blocked PCV system cause similar as its been about 80k since I cleaned the valve and changed the pipes

 

 

Yes, a blocked PCV will cause the engine to pressurise which can blow oil past valve oil seals

And/or up past the piston rings.

 

So it looks like cleaning the PCV first might be cheapest.