Subaru Outback Forums banner

1 - 17 of 17 Posts

·
Registered
Joined
·
79 Posts
Discussion Starter #1
2016 2.5 limited with 57k miles. Just had service done at 55k. This morning got a puff of grey smoke out the exhaust. Not condensation smoke. Smells like exhaust. Goes away immediately. This is probably the 4 time this has happened this year. 2nd time in a little over a month. Car acts fine, still gets around 540 miles per tank. No hesitation. First thought overfill of oil. Checked it and it’s just below top circle. Coolant was way above the full line. For some reason subaru decided to refill coolant a lot. I removed some today back down to just below full line when cold. It only seems to do it after car has sat and is a cold start. Never does it when it’s been driven all day. No smoke while driving. Have not noticed and oil consumption. Check oil regularly with no loss. I’m stumped. Any ideas why I get this puff of smoke every once in a while.
 

·
Registered
Joined
·
17,035 Posts
when there's any odd thing with the car - always check coolant by looking in the radiator, you can't trust the line on the overflow bottle to always accurately reflect actual coolant volume.

any extra cranking time required to start the car?
 

·
Registered
Joined
·
79 Posts
Discussion Starter #4
Ivytech- smoke was grey. Not too dark and dissipated right away. It’s a short burst of smoke.

1 lucky Texan- no extra crank time at all.
 

·
Registered
Joined
·
28 Posts
I wouldn't be too concerned, if it happens only when starting cold, probably just some residual fluids burning in the exhaust system, while catalytic converter is still cold.

During cold starts, engine emits far more particulate matter and pollutants than when warm, because a cold catalytic converter is much less efficient until it warms up.
 

·
Registered
Joined
·
79 Posts
Discussion Starter #10
I bought it brand new. Never had an issue with it. Not sure if I am able to do this. Admins if I can’t please delete this and I’m sorry. Here is what I’m referring to. This is not my car though. Mine is doing the same as this. See. Puff of smoke and gone. Only does this every once in a while.

 

·
Registered
Joined
·
31 Posts
Just curious, how many holes are on your oil check stick? Mine has 3, the upper hole would be over filled. Just checking the simple things first.
 

·
Registered
Joined
·
2,169 Posts
The admins should definitely NOT delete this thread. It is highly important.

I bought it brand new. Never had an issue with it. Not sure if I am able to do this. Admins if I can’t please delete this and I’m sorry. Here is what I’m referring to. This is not my car though. Mine is doing the same as this. See. Puff of smoke and gone. Only does this every once in a while.

https://youtu.be/QKZrJlI8xYE
The problem in that video is engine oil overfill. If I check my oil right after the car has been running (within about 5 minutes), the dip stick will show an incorrect low level. When I check the oil while the car is cold and on level ground, the dipstick shows an oil level right where it should be. The oil needs to settle down into the pan.

Regarding your coolant, it was easy for the grease monkeys to overfill if they topped off while your car was hot or warm. That is my guess why the coolant level shows too high. (I don’t even bother checking coolant level when the car is hot or warm, because I know it is wrong.) I see a trend here. Most likely, the shop topped off your two main fluids when your car was hot or warm.

By the way, your problem is a prototypical example of why I do my own maintenance. These are two basic things a shop should never get wrong. Imagine how they can bungle the more complex stuff.
 

·
Registered
Joined
·
2,211 Posts
Heh, for those that check their oil regularly, perhaps this is another reason not to obsessively keep the dipstick reading at F (I keep it roughly in the middle). Are you checking oil on a cold engine and a very level surface? It can be tricky to get an exact reading on Subarus because they're so sensitive to levelness. As for coolant, there's no harm in "overfilling" that AFAIK, but good suggestion to check the radiator (only when cold).

Similar thread:
https://www.subaruoutback.org/forums/109-gen-3-2005-2009/440674-white-smoke-3-0r-4.html#post5065282

Just curious, how many holes are on your oil check stick? Mine has 3, the upper hole would be over filled. Just checking the simple things first.
The 3.6R dipstick has a holes for L and F and a dimple about 1/4" above the F mark, the 2.5 does not have this dimple. I've been unable to find an official explanation for it.
 

·
Registered
Joined
·
79 Posts
Discussion Starter #14
Well it smoked again today. It’s odd. It’s a puff and then gone. No odd smells. Oil levels checked and they are good. I’m wondering 2 things. Pcv valve or valves rings. Those are the 2 things I keep reading about. Can’t really find anyone with a 2015 and up with this problem. Weird because it doesn’t happen every time. Only once in a while. I’m stumped
 

·
Registered
Joined
·
692 Posts
I suspect it is one of your valve stem seals allowing a tiny amount of oil to seep past it into the cylinder when that one valve is in the open position after you turn off the engine.

If it was my vehicle with this problem I would not be concerned as it is unlikely to cause any major problem in the short term.

Seagrass
 

·
Registered
Joined
·
298 Posts
I suspect it is one of your valve stem seals allowing a tiny amount of oil to seep past it into the cylinder when that one valve is in the open position after you turn off the engine.

If it was my vehicle with this problem I would not be concerned as it is unlikely to cause any major problem in the short term.

Seagrass
I agree I wouldnt worry too much about it, as long as fluids are full and clean
 

·
Registered
Joined
·
4,343 Posts
I'm with the others here; I wouldn't be too concerned.

But if you want to get some assurance you're OK, it's a very cheap and easy diagnostic to pull the spark plugs and inspect them. It's not likely to yield much information, since it's just an occasional short burst of smoke. But if you do see that one plug or one bank of plugs looks different than the others, it can give a clue about what's going on. There's lots of information you can Google about interpreting in-service spark plugs.
 
1 - 17 of 17 Posts
Top