Blue smoke on startup

nord

Veteran Member
Joined
Mar 5, 2010
Location
Southern Tier NY
TDI
All turned back to VW. Now a 2017 Hundai Tuscon. Not a single squalk in 10k miles.
I'm curious. Have you ever considered unhooking the intake pipe from the intercooler just for snits and giggles? I don't mean heading out on the road. Only for a short interval at startup to see whether you have any smoke.

Two advantages here... You should see raw oil being pushed up the pipe if the turbo is leaking and there should be no puff of blue out the exhaust unless there's another source of oil. (Obviously I can't rule out a bad seal on the exhaust side of the turbo.)

Assuming no appreciable oil from the intake pipe and still a puff of smoke, then there's obviously more to the story. Are you absolutely certain this is oil smoke? If so, then there's little question that you have a problem. Given your description it's fair to assume that the oil is migrating from the top end of the engine. This, of course, implicates valve guides as a general rule but another possibility has been overlooked.

Your head may well have a crack or porous casting on either the intake or exhaust side. If a minute crack, then the buildup of heat would very possibly close off the passage of oil due to expansion and then no more smoke. In the case of a porous casting or a minute crack I'd expect a small puddle of oil in either the exhaust or intake area after a period of rest. Oil smoke as the engine started but not enough loss after that point to cause noticeable smoke. Either way there wouldn't be enough oil migration under normal operating conditions to cause excess smoke. You'd only see it after a period of time when the engine was off and oil had a chance to migrate and puddle.

You speak of oil use over time. I don't care what others say, oil use over 10k miles should be all but unnoticeable. When one speaks of "only" a quart over that time I get uneasy as there is a problem. Maybe not a major problem, but a problem all the same.

I wish you well in your quest. Sometimes these "minor" problems are very difficult to diagnose. Not that I recommend it, but my guess is that if you bolted up a new head the problem would disappear. And I'd further bet that an X-ray or dye migration test of the old head would lead you to the problem very quickly.

In other words I don't hold out much hope that your turbo is pumping oil into the intake or exhaust... Not that I would wish this to be the case anyway.

Good luck!
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Okay. I did the intercooler test. Looks like it still does smoke. And besides, I didn't see any oil squirt.

I've never said this is oil smoke. I'm not sure of it's origin. If this would be cracked cylinder heat, wouldn't I be using way more oil, when the oil is being pushed with pressure by the oil pump, especially when driving harder?

What I thought it might be a bad coolant or fuel temperature sensor causing mixture too rich. I checked multiple times with VCDS, looks like all the sensors are okay.

The next thing I think it might be a leaky injector causing a leakdown when it isn't running.

As for swapping the cylinder head, this involves much money and labour. Besides, I'll need to source a good one. What I'm sure is that my camshaft and lifters are in really perfect shape, I don't think I'll find similar shape one in the salvage yard. Messing with the injectors swap again involves a ton on seals, one time bolts, gaskets etc... This car isn't simply worth the effort; it's value is less than ~6'000 EUR or ~8'000 $. Looks like the time has came just to get rid of it.

And yes, this car does use some oil. It's more than a quart and in less than 10k miles. It's such a car. It has always done that, even when I bought it. Probably mu bad luck....
 

nord

Veteran Member
Joined
Mar 5, 2010
Location
Southern Tier NY
TDI
All turned back to VW. Now a 2017 Hundai Tuscon. Not a single squalk in 10k miles.
Henrick,

I really wasn't suggesting that you go out and change the head. I was merely saying that I suspect the head. As to your postulation about oil pressure as you drive harder, it's not the case. Essentially the oil is under no pressure once it begins to dump out of the valve gear. Gravity returns it to the sump.

Again, if oil smoke, then I'd wager a tiny crack or a porous aluminum casting. Oil will migrate through porous material and your morning start would be a great time to observe the result after a night of rest.

Once started and running it will make no difference how you drive as the oil will continue to seep, but not to any noticeable extent.

As to the cost to repair... I'd not get too worried. You know this devil and other than a puff of smoke and a bit of oil she's pretty tame. Since the problem is mostly a matter of aesthetics I'd very likely opt to do nothing.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Thanks nord.

Now when I removed the IC pipe (it was the upper one before the ASV valve) I found some tiny metal shavings/particles in the pipe. I suspect these are from the crashed turbo intake compressor wheel. Although the IC plumbing was cleaned (IC itself was replaced with another one) looks like some particles were still left in there.

Now my question. There's a high chance some of these got their way to the cylinders. Will they do damage? Is there any possibility they will be ejected with the exhaust gasses or will find their way through the piston rings down to the oil sump and will be caught by the magnetic drain plug? Should I loose my sleep about this finding?

The particles I found were no larger than 0.5 mm in duameter.
 

nord

Veteran Member
Joined
Mar 5, 2010
Location
Southern Tier NY
TDI
All turned back to VW. Now a 2017 Hundai Tuscon. Not a single squalk in 10k miles.
Henrick,

Aluminum or steel flakes? If they got to the high side of the intake, then it's a pretty sure bet they got to the cylinders.

If aluminum, then probably not much of an issue. If steel I'd have some concerns. Half a mm is pretty big stuff and steel flakes may not play well with the reciprocating components inside your engine.

And no as far as finding their way into the sump unless they do quite a bit of damage. Rings will prevent this. As to ejection out the exhaust, this is likely. The question is what damage was done before they departed.
 

Ski in NC

Top Post Dawg
Joined
Jul 7, 2008
Location
Wilmington, NC USA
TDI
2001 Jetta ALH 5sp stock
Once a compressor wheel blows, and chunks go into intercooler, air flow really drops off (due to dead turbo) and chunks tend to stay put. Since you replaced intercooler with new one and cleaned out pipes, little chance of anything significant getting through to motor. The intercooler does act somewhat as a debris trap.

If your only issue is a puff of fuel smoke on startup, live with it, it's not a big deal.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
I haven't checked the ones I found/cleaned but I still have the blown turbo. I took a magnet to check and neither the housing nor the compressor wheel are being attracted by the magnet. So I guess they both are either aluminum or some kind of alloy...
 

James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
Henrick.....And yes, this car does use some oil. It's more than a quart and in less than 10k miles. It's such a car. It has always done that, even when I bought it. Probably mu bad luck....

If i remember the oil you are using although synthetic does seem to burn more than other similar weight oils. See Bob is the Oil Guy. There is nothing wrong with the oil as you have had no cam shaft wear.

Take a look at this link. Just some food for thought.

http://forums.tdiclub.com/showthread.php?t=329533&highlight=ccv+2006

Is it possible your pumping a lot of oil thru the ccv.

Just a thought.

Edit, Here is a possibility. Maybe the plug fell out of the injection shaft oil port
 
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Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Injection shaft? You mean the injector rockers shaft, right? It might be possible as well. Unfortunately, it's more likely it's the oil port of #1 injector. CCV on this engine is slightly in different location that BRMs do have. I bet it's like BEW instead:

 

James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
Inside the valve cover there is a small flapper valve that probably allows one way air movement. Might want to have a look at that as well. Could pull the hose there on top after warming up the car and do a visual for excess oil????
 

James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
No. I don't think so since it would not be the conditions under which you would normally operate. Just pull the hose and check for abnormal amounts of oil. You could add clear vinyl hose( with the reinforcement braiding so it doesn't collapse) in a loop and visually check while it is then running.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
I checked the CCV. It isn't the source of oil to the intake, I'd say.

Now I was driving with cracked turbo outlet pipe for more than 1,500 miles. The crack was on the pipe which is the first on the turbo. Today I got a replacement and decided to fix these things (my fuel economy was really down, it was smoking like a train and had absolutely no power & constant limp mode leaving alone the fact it was sounding like an air blower when I was accelerating).

I took the upper IC pipe off just to get to the pipe which is cracked. I found much of dry soot on the upper IC pipe, ASV valve/flap, EGR valve. I'm sure the dry soot is also present in the intake manifold, as well as on valves. I checked my exhaust pipe and rear bumper cover - they were covered in soot too due to excessive overfuelling.

Now does anyone have any idea how should I clean all that mess? Should I do an Italian tune-up or is removeing the intake manifold my only possibility to clean the mess?

Oh, and after fixing the cracked turbo pipe, it still smokes the same.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
No more cracked pipes. All looks good. Unfortunately, I got fed up with this car and its problem. The car's for sale now.

What makes the matter worse is the blue smoke on startup. People who are interested in the car simply walk away when they see the smoke. Some of them whispered it's worn out rings so they're staying away etc etc.

Now since the intake and exhaust manifolds are carboned up due to driving with overfuelling condition for some time, the car developed black smoke on heavy acceleration with no load.....

Any tips or ideas on how to fix (or reduce) the blue startup smoke problem or hints on selling the car are really appreciated.
 

smcnair

Active member
Joined
Oct 19, 2008
Location
toronto
TDI
2006 A5 sedan
I've been going through about a 2 year cycle of trying to figure this one out, giving up, try again...A couple things I haven't seen suggested here:


1. Very interesting thread I just came across (first and last post in particular):
http://www.honestjohn.co.uk/forum/post/index.htm?t=76275
It makes some sense that it could be very very small amounts of coolant seeping in through the head gasket when the engine cools (cylinder head not as tight since aluminum shrinks faster and more than the bolts that hold it down). The trace amounts of coolant make the diesel ignition a little worse, just enough that some doesn't burn fully. Once warm, the head/gasket is tighter and doesn't allow leakage or it still leaks but the diesel ignition is more efficient and not affected.


2. Post #7 by jsrmonster here: http://forums.tdiclub.com/showthread.php?t=321874&highlight=startup+smoke
I have tried this and couldn't find one cylinder that was much worse than the other. Another option (a bit scary) is to start up with the glow plugs out and set up a video camera to see which lets out more smoke. I haven't tried this, too risky
 
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D-Cell_Mekanick

Veteran Member
Joined
May 23, 2009
Location
Sandwich, IL
TDI
2015 Honda Civic SE
I've been going through about a 2 year cycle of trying to figure this one out, giving up, try again...A couple things I haven't seen suggested here:


1. Very interesting thread I just came across (first and last post in particular):
http://www.honestjohn.co.uk/forum/post/index.htm?t=76275
It makes some sense that it could be very very small amounts of coolant seeping in through the head gasket when the engine cools (cylinder head not as tight since aluminum shrinks faster and more than the bolts that hold it down). The trace amounts of coolant make the diesel ignition a little worse, just enough that some doesn't burn fully. Once warm, the head/gasket is tighter and doesn't allow leakage or it still leaks but the diesel ignition is more efficient and not affected.


2. Post #7 by jsrmonster here: http://forums.tdiclub.com/showthread.php?t=321874&highlight=startup+smoke
I have tried this and couldn't find one cylinder that was much worse than the other. Another option (a bit scary) is to start up with the glow plugs out and set up a video camera to see which lets out more smoke. I haven't tried this, too risky
I would doubt the engine would start with the glow plugs removed. Might try a leak down test to see if that can help determine if a cylinder is weaker than the others. Or you can pull the glow plugs an do a hydrostatic check of the cooling system. This involves pressurizing the cooling system to see if it drops pressure and then slowly rotating the engine to see if any coolant comes out of a cylinder at the glow plug opening.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Finally sold the car. Not for a great price, but the car wasn't mint either. Probably bad luck. I think it was better to loose some money instead of keeping it for a year or so and loosing even more money on repairs and resale value....

Problems I or the previous owner had:
DMF, turbo, door wires, blue smoke, odd #4 cylinder injector reading, alternator pulley, EGR valve, intercooler pipes blowing up, various central locking problems, heated mirrors problems, clutch engagement or master/slave cylinder problems. But... Most of these were fixed except one thing I could do nothing about: body rust. I was jealous seeing way older cars looking much better than mine.

No EGR cooler problem. Thank God!!! Cam condition was questionable but it wasn't a catastrophe for sure.

What's sad is that I've spent much money on suspension refresh and TB just before the sale.

All in all, this one was (too) expensive car to keep and maintain. PD design is a bit fragile. No more VW TDI. I'll start looking for a turbocharged gasser from VW probably...

Thanks everyone who helped me. I still believe I'll keep visiting these forums and helping people about things I might know.
 

Scintilla

Member
Joined
Dec 11, 2010
Location
Ontario
TDI
2006 PD WagenRocket, 2000 Golf, formerly an '86 Jetta Turbo Diesel, Diesel Rabbit
Blue Smoke On Startup . . .

Oh yeah, same situation on my '06 PD Sportswagen. Told that I need a new turbo as there is a seal gone and these are non-rebuildable. Who designs this s%!t? Mechanic seems cerebrally competent and agrees that guides and seals are the most likely culprits because the oil seems to be IN THE CYLINDER AT STARTUP. Also, if you start it and burn off the oil, the next startup will be clean - no matter how long you wait. This is because the seals/guides have no additional top-end oil load to flood the valve stems. That is the key to the diagnosis. Still gives 1100 hwy km/tank and no blue fog while driving. I think it uses less than 1 liter of oil between changes. I will have the turbo replaced under aftermarket warranty, but I don't think I'll lift the head just yet. These cars are great on fuel but EXTREMELY expensive to fix. A dealership's dream! Makes you yearn for the days of the Merc W123. Just sayin' . . .
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
You're using no significant oil between changes, getting good fuel economy, didn't have to do any head work or replace the turbo. So what was expensive?

This week my mechanic put new valve guide seals in my '02, in part because it smoked a bit on cold start and oil consumption had increased to a liter in 5000 miles or so. But the engine has 264K on it, has never been apart, and has been making twice stock power for the last 100K. I don't think I can characterize that as a dealer's dream. This is one of the most durable and reliable cars I've ever owned, and I've driven it further than any other car.

It's true that variable vane turbos are generally considered not rebuildable, but they last 200K+ miles in normal use. I don't think that's an unreasonable replacement interval, as it's beyond what many consider the useful life of a car.
 

James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
You're using no significant oil between changes, getting good fuel economy, didn't have to do any head work or replace the turbo. So what was expensive?

This week my mechanic put new valve guide seals in my '02, in part because it smoked a bit on cold start and oil consumption had increased to a liter in 5000 miles or so. But the engine has 264K on it, has never been apart, and has been making twice stock power for the last 100K. I don't think I can characterize that as a dealer's dream. This is one of the most durable and reliable cars I've ever owned, and I've driven it further than any other car.

It's true that variable vane turbos are generally considered not rebuildable, but they last 200K+ miles in normal use. I don't think that's an unreasonable replacement interval, as it's beyond what many consider the useful life of a car.
Interested to know if this solved your oil burning or smoking on cold start up. If your replacing the seals one has to be careful not to compress the spring to far or you contact the the new seal when replacing the inserts. I replaced one bad seal without removing the head but you do lose some spring to valve stem travel( when compressing the spring) since you rely on the piston at top dead center to hold the valve almost closed.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
No. Mr. Chill pulled the seals yesterday and found the valve guides excessively worn, especially the intake valve guides. So we're pulling the head and putting on a ported head with dBilas cam and double valve springs. I guess after 264K, 234K chipped, 90K running 26 PSI finally took its toll. Ironically the valve guide seals weren't in terrible shape, and it was using about a liter of oil every 4000 miles. Not terrible.
 
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