NOOOO i have blue smoke under load....

[03cupra]

Right recently had a turboback miltek exhaust fitted with decat.. 3" downpipe going into 2.5" exhaust

Yesterday morning finished a nightshift, i put my foot down to show the guys what it sounded like and i got a phone call telling me i had some blue smoke under acceleration.

I'v noticed nothing on idle, and no noticeable drop in oil level

Any suggestions?

cheers guys, please no bad news lol.

car is LC standard map

 

[brad_barker12]

If your not losing any oil then I wouldn't worry. Keep an eye on the oil levels from now on, if you get a noticable drop then start worrying

 

[03cupra]

ok sure, but i shouldn't be getting any smoke out the exhaust, so surely eventually this will become a problem?

I've done plenty of searches on here and from what i can gather changing the back pressure on the turbo will show any leaking valves, rings etc... i imagine this smoke will only get worse over time...

 

[tom t]

Or it's the lads at work taking the P!

 

[03cupra]

I wish it was, they're both car guys, wouldn't wind me up about something like that... One of em has a pre facelift LC, reckoned it was only a puff when i floored it in first gear... I just can't see that blue smoke from the exhaust, however little, would be something not to worry about!

 

[BigJase88]

Im guessing you were ragging it away on a stone cold engine by the sounds of this

Blue is oil so keep an eye on it, full boost from cold is a bit silly

 

[03cupra]

yeah your absolutely right mate.... id just finished a 12 hour night shift and the guys asked what the exhaust sounded like and i put my foot down not thinking about it..

i know theres probably nothing worse i could to to a turbo!

 

[brad_barker12]

I wish it was, they're both car guys, wouldn't wind me up about something like that... One of em has a pre facelift LC, reckoned it was only a puff when i floored it in first gear... I just can't see that blue smoke from the exhaust, however little, would be something not to worry about!

could be excess fuel, mine sometimes bangs on gearchange when giving it the beans sometimes a little black smoke comes from the exhaust when it does which is fuel. not really anything to worry about as long as its not pouring out the exhaust.
could also be condensation burning off.
if it was oil it means your burning it or your turbo is on its way out, either way there would be a noticeable drop on the dipstick

Im guessing you were ragging it away on a stone cold engine by the sounds of this

Blue is oil so keep an eye on it, full boost from cold is a bit silly

he might of let the car warm up before he took it out.
but if the OP did push the car hard while it was cold I wouldn't from now on. for any car its not very good for it let alone a turbo. need to let the oil get up to temperature before using your right foot otherwise you will need deep pockets to fix the potential damage you could do ie turbo/engine

 

[03cupra]

Valve stem seals could be your problem, when the car is turned off in the night the oil left in the crankcase is left there to drain, some of this oil can seep past the valve stem seals down the valve stems and into the cylinders over night, as the engine warms up the next day this oil will be burned and expelled as blue smoke from the exhaust.

Turbo smoke is normally most apparant when the engine and oil is warm after a drive let the car tick over for a few minutes then give it a rev, if you get blue smoke then its more than likely that the oil control rings/seals on the exhaust side of the turbo are leaking which will seep oil into the hot exhaust housing and when you rev it the smoke will be blown through the exhaust.

If you get smoke on gear changes this can be caused by the thrust bearings in the turbo being damaged and allowing vertical play through the core of the turbo, this is most apparant when you change gear or leave off the throttle and put it back down because the change from boost to vacuum puts strain on the shaft which will move if the bearings are damaged, seep oil and give you smoke.

Piston ring smoke is mostly seen on a warm engine and under load up a hill for example on constant throttle. It can also be seen after a long over-run down a hill letting the car coast in 4th for example and then revving it at the bottom of the hill, the vacuum in the engine can cause oil to be sucked past the piston rings. Worn piston rings can also cause heavy breathing and can push oil out of the crankcase breather.

Hope this helps."

Sorry for the copy and paste - typing all that myself on a Tuesday (Monday) morning didn't grab me...

Got the above from the Audi forum, some guy with an A3 1.8T, if the above is correct then piston rings are going... i think for my own piece of mind i need to do compression and leak tests to see if theres something serious going on

 

[03cupra]

or valve stem seals given it was from cold when it was noticed... i am on a night shift tonight, so ill check the car on start up tomorrow and again when i get home and go from there..

 

[03cupra]

Uprated or non genuine exhaust system. Reducing the exhaust back pressure with a free flow exhaust system can cause oil leakage from the turbo oil seals, leading to blue exhaust oil smoke.

By putting a 3" downpipe going to 2.5" exhaust on my unmapped LC have i reduced backpressure too much and caused my turbo oil seals to leak?

 

[Kingscote]

I'm guna go with turbo seals! Sounds like a reason to get it rebuilt, or just go hybrid

 

[GlanzaV]

If it was from cold it might even just be condensation in the exhaust, white being mistaken for blue? I suggest getting a mate to follow you for a bit and do a few runs with the oil up to temp.

It's been mentioned above but blue smoke on load sually means turbo seals, if it's blue on over-run I'd say valve stem seals.

I'd also hasten to add that because you've just decatted you might find you're cars always been like this, but it's just more apparent because of the free flowing exhaust. In the good old days when I ran about in Jap imports, the suggestion would be to run a slightly thicker oil, would stop small amount getting passed "slightly" worn seals.

 

[03cupra]

Well after worrying all night, a thorough inspection of the engine bay and repeated up to temp runs no more blue smoke has appeared... However I do seem to have a weeping rocker box gasket and 2 leaking Injectors, could this have cause a bit of smoke? I can only assume the colour was mistaken when I was first informed, unless it really is early stages and only manifests itself when booting from cold or something equally as stupid!

 

[danblowes]

most de-catted turbo cars do give a little blue smoke on lift off (Cossies are well known for it) Just keep an eye on your levels as there isn't anything fundamentally wrong, but booting it from cold is never a good idea.

 

[brad_barker12]

My decatted turbo doesnt give off any blue smoke :S
As said before if it was blue smoke it would mean oil, if it was oil smoke you would have a noticable rise in oil consumption which you have said is fine. Your car may well of smoked a little under hard acceleration, if it was cold it maybe condensation. All this talk of rebuilds is rubbish. Enjoy the car and stop worrying.
As for the rocker cover gasket get that changed

 

[danblowes]

My decatted turbo doesnt give off any blue smoke :S
As said before if it was blue smoke it would mean oil, if it was oil smoke you would have a noticable rise in oil consumption which you have said is fine. Your car may well of smoked a little under hard acceleration, if it was cold it maybe condensation. All this talk of rebuilds is rubbish. Enjoy the car and stop worrying.
As for the rocker cover gasket get that changed

Couldn't agree more , just enjoy the car

 

[GlanzaV]

A little tip my old dad gave me if you're really worried. hold / tape some kitchen towel to the exhaust pipe and run the car. when you take it off you may see some spots, some will be carbon, but if you see wee oily spots then you are getting some oil through the seals. You can obviously gauge how bad it is by how much has passed through.

 

[03cupra]

Cheers guys, I'll keep an eye on everything jus panicked when I heard blue and smoke in the same sentence, haven't been able to get the car to do it since..

I'll certainly get the rocker gasket sorted. With the injectors if there is a leak is there any benefit to upgrading them... I'm a fan of uprate rather than replace... If there is any benefit to the car..