My yard filled with exhaust on start...

Hey... I got a used engine put in my car a year and a half ago and a new
transmission in October... I have a 94 Saturn SC1... I also had the head
gasket on the engine resealed about a year ago...

It's wintertime up here now, and we're getting temperatures overnight of
about -5C or so. When I leave the car for about a day, I let it warm up
before I drive it, of course...

The other day, I did a long highway drive (about 300 miles/500 KM) and then
left the car parked a day or so. I started her up and let her warm up,
popped inside the house, and about 4-5 minutes later, I went out to the
carpark to find the yard FILLED with white smoke. It wasn't the dark smoke
that one typically associates with oil and it didn't smell like it either
(knock on wood)... it was thick and white, and kind of just 'floated' there
like a cloud.

However, when I FIRST started her up, I didn't even notice. It's only after
about a minute of idling in the cold that the exhaust starts to fume out
heavily. I also notice a lot of condensation on the pavement where the
muffler hits, so it looks like something with water was burning up.

Even stranger, is that after driving a half mile or so, the exhaust stopped
heavily churning out for the rest of the night, including when I parked and
let it run at idle at my destination 20 minutes later.

Any ideas of what this could be?

Am I possibly experiencing the 'coolant milkshake'? I looked in the coolant,
and its pretty solid green, murky, not at all discoloured, as I've heard the
'milkshake' looks like. And it's fairly close to being filled to the top
(it's about half an inch to an inch below the top of the reservoir).

Oil level was OK, and clean too (only drove it about 1500 miles since my
last change).

After this bizarre behaviour, I did the 300 mile drive again, arrived at my
destination problem-free.

Was this possibly just an oddity?

I also replaced my PCV valve last week. I assume I did it right, because it
looks pretty straight-forward. I checked it, and it didn't seem loose or
anything. Could this be the source of the problems?

I've also recently passed an emissions test (August).

Thanks for all your help. My biggest concern is that I'll get the coolant
milkshake...because that always seems to lead to destruction, and I'm not
going to get a third engine on this car. The vehicle already has 197000 KM
on it, engine gots 120000 KM and tranny gots about 165000 KM.

 

I'd watch your coolant level. The engine might be sucking coolant
into a combustion chamber.

Ken

 

WAH!!! NOOOO!!!!!

If this is indeed the case, am I headed for big trouble eventually? Is there
any easy way to fix it? Does it mean it's going to start happening the other
way around too (i.e. oil into the coolant line)?

I'll check it later on, I just did a 4 hour drive, so I'll see if it is any
lower than it was when I left...

 

This all sounds fairly normal. Likely it was a windless day, and
the water vapor produced by burning the gasoline just hung around
rather than dissipating.

When you first start the exhaust system is cold and the moisture
condenses in there. After the exhaust system warms up the moisture
begins comming out. Then, once you hit the road, the engine warms
up enough that it leaves a warm air wake (from the radiator), so
that the exhaust doesn't condense so readily.

 

This could be true, too. Time will tell.

Ken

 

IF this is the problem, my guesstimate would be that it wouldn't go
the other way. IF it's sucking coolant in, it indicates that the
problem is in an area where the coolant leak is exposed to vacuum
rather than compression or the crankcase. That doesn't mean that a
gasket failure could happen in one place and then give out in another
later. I wouldn't get too excited yet. Read Dan Hick's comment, as
that is also a reasonable explanation.

Ken

 

That could be a coolant leak into the engine - normal cold-weather exhaust
fog doesn't usually persist like that, though I suppose under some
conditions it could.

The last (probably the only, actually) car that I saw putting out clouds of
white smoke from burning coolant was also putting out a nasty, acrid smell..

 

Yes, it COULD be a coolant leak, but it definitely IS possible for
"normal" cold-weather exhaust to persist like that, given the right
conditions.

If it's a coolant leak then it will be obvious as the coolant level
drops. If the coolant level drops then he should check into it, but
if the coolant level holds steady then he should find something else
to worry about.

 

I'm praying that the problem was just moisture burning off when the car
started to warm up. However, I don't think this was it, because there was a
little bit of a burning-in-the-eyes, and a smell, to the smoke, and it was
thicker than steam, for sure...

But I just checked the coolant level after this 500 KM drive (300 miles or
so) and its at the full-cold mark when just starting up... so it still looks
like it's OK. The full cold mark is the thing in the reservoir where there's
a little plastic line that crosses the opening, about an inch below the top,
right? It's just about that little piece of plastic.

And indeed, I started the car again recently, in a garage that was a little
warmer than the outside, say about 8 to 10 degrees Celcius (a little above
freezing in Farenheit terms) and I let it sit for about three minutes in the
garage... The exhaust was visible from the muffler, but it was only minimal,
and wasn't 'floating' in the air as the other kind was. I think it was just
normal for starting up the car.

I'm thinking it could be a rich mixture that occurred, and that it burned
off too much gas... I'm guessing that because of the colour and the smell
and the way it 'floated' in the air. What wuold be the signs of it benig too
much gas, versus coolant burning off?

Thanks a lot guys... starting to get somewhere here. You guys on
r.a.m.saturn are the best! I have done so much because of you.

 

Bad coolant temperature sensors are somewhat common on the S-series cars,
and can cause an overly rich A/F mixture. If the exhaust smelled gassy,
that's probably what it is. If it was burning coolant, from my experience
the smell is distinctly unlike any normal exhaust, rich-running or
otherwise..

 

The way exhaust moisture behaves is highly variable, depending on
the precise conditions of temperature, humidity, and wind. If
humidity is relatively low the fog dissipates fairly rapidly,
whereas if the humidity is fairly high it will hang around. The
slightest bit of wind will dissipate the fog, but if it's perfectly
still it will tend to hang around.

The fact that you CAN'T reproduce the fog suggests that it's
ordinary exhaust moisture, vs something like a coolant leak. But in
any event, watching the coolant level won't hurt.

 

Generally it goes like this. Black smoke is fuel (ie, too rich). Blue smoke is
oil burning. White smoke is coolant burning. Each has a smell associated with
it.

 

there is nothing wrong with your car. the smoke is condensation, water,
in the muffler, in the gasoline, in the air, my jaguar always does that
oncold days too. so do all cars, just some more then others, this is
typical of european cars on cold days. you can buy a gasoline dryer at
a boating facility or marina. might try to lean the air misture screws
to 1 1/2 turns out. make sure the choke KICKS OFF after about a 3
minute warm up Slam it to the floor and release then wait for slow
idle. your carburator is simply TOO RICH in gas. always use the lowest
octane fuel. if you can afford champion gold platinum plus spark plugs
use them. also use STP oil treatment, won't hurt. change the air
cleaner, it might be wet with water, condensation, moisture in the fuel
system. this problem is
embarassing for you AND THE FUZZ

http://community.webtv.net/bwclaypool/doc

 

might try to lean the air misture screws

Ummmm, yeah..........
This car doesn't even have a carburetor.........
And I've never heard of anybody ever liking champion spark plugs other than in
the lawn mower......and spark plugs don't make a performance difference
either......