2G white smoke from tailpipe

[Allen2g]

im gonna go nuts!! so white smokes been coming out of my tailpipe, compression test was good so i dont think its the HG, i have no cooling issues as well. I went and checked the stock t25 & there was in and out play(LOTS) so i suspected it being the problem. Went ahead and replaced it with a small 16g(0 shaftplay), replaced my waterpump/belt as well and theres still smoke even after all that.
could it be exhaust leak? boost leaks, pcv? ahh

 

[stillrunning]

How many miles on the engine?
Valve seals are a very common issue with oil smoke, bad intake valve seals will allow oil to weep into the cylinder through the valve stem & exhaust side will allow it to weep into the exhaust port/manifold.
A slightly blown head gasket to the cylinder will usually pollute the cooling system which you would be able to see in a dirty coolant and distinct burnt/fuelish/combustion smell in the coolant.
Just like the cylinder can suck coolant in it will also blow compression into your cooling system.

 

[Allen2g]

How many miles on the engine?
Valve seals are a very common issue with oil smoke, bad intake valve seals will allow oil to weep into the cylinder through the valve stem & exhaust side will allow it to weep into the exhaust port/manifold.
A slightly blown head gasket to the cylinder will usually pollute the cooling system which you would be able to see in a dirty coolant and distinct burnt/fuelish/combustion smell in the coolant.
Just like the cylinder can suck coolant in it will also blow compression into your cooling system.

Engine has 150k, i honestly almost did not believe the 175 175 168 165 compression. Its amazing, it blows my mind . I see no oil in coolant and no coolant in oil so i dont think its an HG.
Is there a way to test whether my valve stem seals are okay or not? Would bad stem seals affect compression?

 

[curt-s]

No, seals are past the valve seat. Compression happens in the cylinder. anything that has an entryway into the cylinder can affect compression.

rings - leaking past rings
valve seats - leaking past valve seat
spark plugs - leaking past threads, though only really if your plugs are out or threaded in only a couple threads. even a compression tester threads and seals well enough
head gasket - leaking into adjacent cylinder, coolant or oil channel, or, in significant instances, completely outside the engine

generally to see if your seals are good you need to see the backside of the exhaust valve and port.

side question, was this the 2g I saw on kijiji recently? "testing waters"?


also, its minus cold as hell here.. every vehicles exhaust creates a visible white cloud, regardless of condition of engine. it's a byproduct of the vapour in the gas.. unless it is blue you aren't going to be able to diagnose much in winter unless you have a heated garage at +25C.

 

[Allen2g]

No, seals are past the valve seat. Compression happens in the cylinder. anything that has an entryway into the cylinder can affect compression.

rings - leaking past rings
valve seats - leaking past valve seat
spark plugs - leaking past threads, though only really if your plugs are out or threaded in only a couple threads. even a compression tester threads and seals well enough
head gasket - leaking into adjacent cylinder, coolant or oil channel, or, in significant instances, completely outside the engine

generally to see if your seals are good you need to see the backside of the exhaust valve and port.

side question, was this the 2g I saw on kijiji recently? "testing waters"?


also, its minus cold as hell here.. every vehicles exhaust creates a visible white cloud, regardless of condition of engine. it's a byproduct of the vapour in the gas.. unless it is blue you aren't going to be able to diagnose much in winter unless you have a heated garage at +25C.

I see, i guess its either my turbo or valve stem seals thats causing the smoke.
I see some oil around my manifold, heres a few pics. & thats true, but im pre sure im burning some oil with a mix of normal condensation

 

[1990TSIAWDTALON]

I still think oil rings and hoping its just stem seals.
FWIW...we replaced VS seals on a head and the wore out GUIDES were the problem. Seals lasted about a month then it smoked again and especially at the line, brake boosting.
Something to ponder.

 

[Allen2g]

I still think oil rings and hoping its just stem seals.
FWIW...we replaced VS seals on a head and the wore out GUIDES were the problem. Seals lasted about a month then it smoked again and especially at the line, brake boosting.
Something to ponder.

Hoping as well its just valve stem seals or turbo as those are easy enough to replace. I think i can rule out the HG and rings as my compressions look fine. Ive seen some threads saying a leaky valve cover gasket can cause oil around the exhaust manifold but i dont see any dripping from the cover itself. Ill also replace the sparkplugs.
Would a BLT show me whether the seals of my turbo are blown?

 

[1990TSIAWDTALON]

It might let boost into the oil drain, sending pressure up to the VC. You can sometimes here it leaking if so.
Your compression rings may be fine but oil rings are tiny and if ever over heated too much can loose some tension against the cylinder wall, allowing oil to get past is what I was getting at in the previous post.
Crossing my fingers!

 

[curt-s]

also, you will always have a small amount of air leaking past turbo seals, but especially so while cold.no oil pressure or flow behind the seals, thin cold metal shrinks slightly.. so, unless you have a massive amount blowing by them, do not immediately come to the conclusion they're shot.

it comes more with experience and a trained ear how much air should be bypassing turbo seals on a cold test.

either way you would be testing the intake side and your concern should be more focused on the exhaust side if you are worried about that smoking. only way to see that is to pop off o2 housing to see turbine wheel and heat shield, inspecting for oil leakage past seals on THAT side.

 

[Allen2g]

also, you will always have a small amount of air leaking past turbo seals, but especially so while cold.no oil pressure or flow behind the seals, thin cold metal shrinks slightly.. so, unless you have a massive amount blowing by them, do not immediately come to the conclusion they're shot.

it comes more with experience and a trained ear how much air should be bypassing turbo seals on a cold test.

either way you would be testing the intake side and your concern should be more focused on the exhaust side if you are worried about that smoking. only way to see that is to pop off o2 housing to see turbine wheel and heat shield, inspecting for oil leakage past seals on THAT side.

Makes sense, i hit boost on the way to work today and it was puffing smoke as it boost. I think i have some blow by as i had some oil on the stock rubber ic hose that connects to the manifold but i dont think its too bad to the point my dipstick pops out. I had some oil around my exhaust manifold pics at post #29, could that possibly be cause by the turbo? Seen post saying valve cover gasket but i dont see any oil dripping from there so that doesnt make sense

&yeah ill pop off the o2 housing maybe on the weekend or friday and see how that is.

 

[curt-s]

don't remove it unless you have new gaskets. you will need a couple, downpipe and turbine housing. I wouldn't reuse either as variations in surfaces create crush spots and they will never realign right after. you might be able to get away with keeping o2 housing attached to downpipe but it isn't fun. in that case you still need a o2 housing gasket for your particular hot side.

I don't know what youre talking about when you say stock rubber ic hose that connects to your manifold.


oil on your exhaust manifold like that would not be caused by the turbo. I'm also not convinced entirely that it is the byproduct of crankcase pressure forcing hot thin oil past the valve cover seal because the oil is collecting on the opposite side of the exhaust manifold gasket. hot oil will wick slightly so it could be coming from adjacent exhaust ports.

if you're getting excessive smoke out the back I would be pulling the manifold to see the exhaust ports and o2 or hot side to see the turbine wheel and heat shield.

with it being so cold and all exhaust creating a visible cloud it is hard to fathom your concern without seeing it. do you have the ability to record idle, cruise and acceleration?

 

[Allen2g]

The stock upper rubber ic hose that connects to the intake manifold.
Im getting excessive smoke for sure, its a thickish white cloud, doesnt smell like coolant tho so it has to be oil¿ unless im always getting condensation in the system . I can probably get my friend to record me cruising and accelerating later today. But to give you a brief explanation at idle it has a thickish white smoke, again has no sweet smell at all, cruising i can def still see smoke, acceleration smoke puffs out . When revved also, smoke puffffs out

 

[curt-s]

oil, depending on engine load and temperature, usually has a blue tint when burned in an engine and doesnt come out in gobs unless your rings or exhaust valve seals are entirely shot. the former is especially so when the block has oil squirters.

a thick white cloud leads me to believe coolant, regardless of smell, namely because it has a much lower flash point than oil and vapourises quicker.

with us being in the same city, perhaps we can set up a meet and i can take a look. hard to gauge acceptable vapouring out the exhaust in winter but if there are massive amounts that should be pretty evident of a problem.

a cracked turbo center section can be dumping small amounts of coolant into your hot side as well and not show any problem with head gasket. rare since the cartridge is fairly beefy.
cracked head depositing coolant on the backface of the valves..
warped head that doesnt show under a compression test but does after coming up to operating temperature..

if it was just leaky valve seals i dont think you would see big plumes of smoke on accel. i think that would be more evident of a head gasket issue since the water pump is flowing more coolant.

 

[Allen2g]

oil, depending on engine load and temperature, usually has a blue tint when burned in an engine and doesnt come out in gobs unless your rings or exhaust valve seals are entirely shot. the former is especially so when the block has oil squirters.

a thick white cloud leads me to believe coolant, regardless of smell, namely because it has a much lower flash point than oil and vapourises quicker.

with us being in the same city, perhaps we can set up a meet and i can take a look. hard to gauge acceptable vapouring out the exhaust in winter but if there are massive amounts that should be pretty evident of a problem.

a cracked turbo center section can be dumping small amounts of coolant into your hot side as well and not show any problem with head gasket. rare since the cartridge is fairly beefy.
cracked head depositing coolant on the backface of the valves..
warped head that doesnt show under a compression test but does after coming up to operating temperature..

if it was just leaky valve seals i dont think you would see big plumes of smoke on accel. i think that would be more evident of a head gasket issue since the water pump is flowing more coolant.

Oh yeah i read somewhere that if oil is burned in the exhaust instead of engine it comes out as white instead of that blue tint, not sure if its true but if thats the case it rly leads me to the turbo but idk .
If youre down to take a look i can probably come to you for you to take a look aha, thatd be sick.

 

[curt-s]

what oil brand, type, and viscosity are you running?
you mentioned the mileage.. sometimes fresh synthetics leak past old seals & o-rings.

 

[Allen2g]

im currently using penzoil 5w30, its non synthetic. <gna switch up to 10w30 when it warms up
my mileage is quite high but i have really good compression which really blows my mind

 

[Allen2g]

Update: checked my coolant level today and i am burning a bit. Really leads me towards the turbo, not leaking any coolant anywhere so it has to be being burned somewhere which i think is the turbo. Cant be my hg since my comp test seems to be good and i dont see oil in my coolant, vise versa.

 

[curt-s]

i have to say i would be a tad surprised its your turbo just based on what has to occur for coolant in the center cartridge to slip out but it isnt out of realm of possibility. frequent heating and cooling cycles along with vibrations can crack cast iron..

if you suspect it, time to pop it off and inspect it. at the very least you will get a view into exhaust manifold or ports as well.

new gaskets will be needed.. all in the area except exhaust manifold to head if it is multilayer steel (looks like it from pictures) and in good sealing condition.

how are you sure you are burning coolant? i am just trying to think of other things you can check that are less invasive first than pulling a turbo and exhaust manifold off.. it is no "easy" feat (it is annoying and stubborn) and costs a few bucks to put back on. but even if we wanted to check exhaust valve stem seals you would be pulling the manifold anyway.. so i think we all know what your next step is

all this is, of course, assuming that the amount of smoke you have coming out is not due to normal winter conditions or an overly rich AF mixture. neither explains loss of coolant unless you have a rad or hose leak. i had one on lower rad hose when clamp backed off a bit.


still dont know what hose youre talking about.. upper rubber ic hose... bov signal vac line?

 

[Allen2g]

Yeah pretty sure im burning a bit of coolant, it makes sense i am due to amount of smoke. Ill take a vid of it at idle later today. I really dont know where else id be burning coolant other than the turbo or from hg or head cracked. It really cant be the head or head gasket. I have no coolant in oil vise versa, ive driven the car for the past two weeks and have no over heated once. Comp test are also rly good. So i suspect the turbo, its an ebay turbo i bought off someone, it was also claimed as rebuilt. So it seems likely that its the culprit.

Side not: on my defense i was quite noob when i was buying the turbo, new to dsms overall. didnt know it was an ‘ebay’ turbo. If i knew i might as well have bought a brandnew ebay turbo .

Also heres a pic of what rubber hose/pipe im talking about.

 

[1990TSIAWDTALON]

We had an ebay turbo way back in the day that did have a cracked CHRA and allowed coolant to leak. We just coolant deleated the dam thing and ran it as a oil only turbo.

 

[Allen2g]

We had an ebay turbo way back in the day that did have a cracked CHRA and allowed coolant to leak. We just coolant deleated the dam thing and ran it as a oil only turbo.

i was thinking of doing the same but i think it is burning some oil as well, gonna check the oil level later today and make sure.

 

[Allen2g]

More update, so its really warm today and theres little smoke now . I think im just overthinking and tripping out. And the coolant im loosing is i think from my coolant neck and some from my coolant feed to the turbo.. AAAAAAAAAAAAAAAAAAAAAAAH. ahaha.

 

[1990TSIAWDTALON]

Maybe just nornal wear, if there is such a thing for a DSM.

 

[Allen2g]

Maybe just nornal wear, if there is such a thing for a DSM.

, i hope so man. Smoke has never stressed me out this much ahaha

 

[curt-s]

glad to hear!
that rubber hose, now i get it.. the upper intercooler pipe. lots of reasons there would be oil deposits in that vicinity. if you want we can sit down with your beastie and go over things when it is warmer and we are not freezing. just keep an open mind about what may be uncovered

 

[Allen2g]

glad to hear!
that rubber hose, now i get it.. the upper intercooler pipe. lots of reasons there would be oil deposits in that vicinity. if you want we can sit down with your beastie and go over things when it is warmer and we are not freezing. just keep an open mind about what may be uncovered

that would be great aha, there is still smoke which is kinda not normal. Gets worse when it gets colder , still might replace my turbo just for peace of mind aha