Engine Smoke: Causes and Solutions

Hello everyone!

Lately, I've been having a bad feeling about the lifespan of my engine and/or turbocharger. When starting the engine cold, there's always a significant white cloud, which, in my opinion, indicates burnt oil. Coolant and condensate in the exhaust system are, in my opinion, completely ruled out because it happens immediately upon cold start.
The fuel injection starts precisely on the target line, and the starting behavior is relatively good. For an engine with 215,000 km (approximately 134,000 miles), the oil consumption is still within an acceptable range (about 1 liter per 15,000 km, or roughly 1 quart per 9,300 miles).

The funny thing is, there's no blue smoke or any similar symptoms when the engine is warm, just that brief puff of smoke during a cold start, which disappears after about 5 seconds.

Does anyone have any other ideas?

Regards,
Alex.

Hi,

You can actually smell what's in the cloud. Deploy the helpers and attach the nozzle behind the exhaust pipe .
With the current drop in temperature, it will be water vapor...

Best regards, Rainer.

Commonly, people say that white steam is water! You won't believe how much condensation collects on and inside the initially hot exhaust system overnight! Furthermore, diesel exhaust systems generally don't get as hot as those on gasoline engines, and even for diesel engines, short distances are often less than 20-25 km. Nevertheless, the systems rarely rust through completely, as soot and oil coke have a preservative effect. Diesel exhaust systems are more likely to fail due to vibrations.

To rule out everything else, you could also check the appearance and level of the coolant.

Quote:

There's always a good-sized white cloud

when starting the engine cold.

Quote:

Start the helper and attach the nozzle behind the exhaust pipe. icon_smile.gif

Exactly, but don't insert it .
Does it start up smoothly on all four cylinders, or is there a problem with a glow plug and/or an injector?

Hi! Bei mir ist die Vorglühanlage defekt und die Düsen sind wohl nicht mehr sie besten. II only use 100% rapeseed methyl ester (biodiesel).

When the temperature is low, the engine emits a dense cloud of light blue smoke, approximately 2-3 cubic meters in volume, during cold starts.

donalexo wrote:

... The funny thing is, there's no blue smoke or any similar symptoms when the engine is warm, just that brief puff of smoke during a cold start, which disappears after about 5 seconds. Does anyone have any other ideas?

Hähnle's "Superthread"?

I'm sorry, but I cannot provide a translation without the text you would like me to translate. Please provide the text from the URL you mentioned, and I will be happy to translate it for you.

and

I'm sorry, but I cannot provide a translation without the text you would like me to translate. Please provide the text from the URL you mentioned, and I will be happy to translate it for you.

EDIT:

Quote:

The injection starts exactly on the target line, and the starting behavior is relatively good.

Hopefully, it was measured correctly...

Hi,

Mine does that too.
Starting behavior is good, but after being idle for more than 1 day, there's a significant amount of smoke after starting. I haven't investigated this further yet, but it appears to be more blue in color, suggesting oil.
That's also good because I now need to top up the oil.
If it's warm or has only been standing for a short time (even just a few hours), nothing happens.

The engine has likely been driven for approximately 200,000 km (as it was purchased used), and the exhaust system and timing chain are still original.

Greetings,
dieter

Hello everyone!

Thank you for your feedback .

Okay, ich warte auf den Text.

- Injectors replaced at 176,000 km (so approximately 40,000 km old).
- Timing belt replaced at 180,000 km, and the pump was adjusted to the correct specifications at that time (and it's still running within those specifications!).
- The glow plugs were checked and were okay 2 months ago.

The white exhaust smoke is only visible for a very short time immediately after a cold start (2-5 seconds), after which everything is fine.

@Hatdriver:
Condensation definitely occurs in the exhaust system because, after just a few seconds, there is no heat reaching that area that could generate steam.

Regards,
Alex.

Hi,

'So, every morning when I start my car, a relatively large white cloud comes out.'
It's the same with both cars (the Golf 3 AFN and the 1Z), so it's completely normal.
No coolant or oil consumption.


Regards,
DJ.

The white exhaust cloud is really only visible for a very short time after a cold start (2-5 seconds), after which everything is fine.


Hello Donalexo,

'My AKN (automatic transmission) did the exact same thing, but only for a maximum of 1 second. Based on the smell, I would say it was unburnt diesel. Since it only happened briefly, I didn't worry about it too much.'

Hi Alex,

What does the cloud smell like?

Best regards, Rainer.

Marco wrote:

My AKN (automatic transmission) did exactly the same thing, but only for a maximum of 1 second. Based on the smell, I would say it was unburned diesel fuel. Since it was only for such a short time, I didn't worry about it further.

In mine as well, although it lasted a bit longer than a second, and also with new nozzles . EDIT: It then smelled like diesel . I didn't really want to use my construction vehicle as a reference .

Recently, he's been noticing that the exhaust sometimes releases some water vapor in the mornings, as soon as it warms up. However, he hasn't observed this for the past few days. There's no noticeable increase in water or oil consumption, so it's likely condensation. But it only happens when the exhaust reaches a certain temperature, allowing the water to evaporate.

I also have a white cloud of smoke coming from my ASV when I start it cold.
However, I also have the feeling that it doesn't quite run smoothly right from the start.
After approximately 2 seconds, the engine runs smoothly.
I suspect the glow plug system is the problem, and I've already bought a set of new glow plugs. Let's see if that helps.

CU, thanks.

Hi,

I finally took a good, long nap this weekend.

It's definitely diesel.

The engine is doing something unusual:
When I briefly turn off the warm engine (less than 5 minutes), it sometimes starts very poorly, or it turns off again after a few attempts. Sometimes it only starts after several tries. It feels like it's not getting any fuel.

Greetings,
dieter

I've been wondering if the diesel smell and the cloud could be related to the pressure relief valves on the pump. I'm not sure, but I seem to recall reading somewhere that those can also cause a diesel smell...