[saqueme]

So for the past few months I've noticed a sweet smell coming from my exhaust ONLY when the engine is cold. Never once it's warmed up. It's weird, my oil has always looked clean and I haven't had to top off my coolant in 3 months. It hasn't been that big of an issue, but it's still concerning as the smell is strong and will reach me if I leave my door open after a few seconds. I've tried to look into previous posts, and some said it might not necessarily be a headgasket but they never really could answer my issue, anyone have any advice on this?

[nsjames]

is coolant going missing?

[Brian86]

It's a head gasket.

When you shut the engine down coolant pressures rise a little and cylinder pressures drop to atmospheric. It's pushing coolant into the combustion chamber where it accumulates and waits for you to restart it.

[saqueme]

Originally Posted by Brian86

It's a head gasket.

When you shut the engine down coolant pressures rise a little and cylinder pressures drop to atmospheric. It's pushing coolant into the combustion chamber where it accumulates and waits for you to restart it.

How serious do you think that is? Like I said, I haven't had to refill it in months but the smell is strong.

[saqueme]

Originally Posted by nsjames

is coolant going missing?

I haven't checked recently, but it hasn't really lost a ton. I haven't gotten a warning and its been 3 months since its been topped off

[nsjames]

Originally Posted by saqueme

I haven't checked recently, but it hasn't really lost a ton. I haven't gotten a warning and its been 3 months since its been topped off

then figure out where the coolant goes.
if it's not an external leak it's in the motor and that's bad.

[bmwbob89]

If its not an external leak and your not having any other issues leave it alone until you do. Unless you have money and or time to spend before you really need to.

[saqueme]

Originally Posted by nsjames

then figure out where the coolant goes.
if it's not an external leak it's in the motor and that's bad.

it's definitely going into the combustion chamber somehow

[nsjames]

Originally Posted by saqueme

it's definitely going into the combustion chamber somehow

then it looks like you should plan on taking yours apart or replacing it.

[Brian86]

There just isn't any other way for coolant to get into the exhaust. If you're sure that's what it's doing on startup, it's the head gasket.

Eventually the leak will get bigger and it will start pushing compression into the cooling system. This will result in local overheating initially then coolant getting blown out the release valve. Finally a complete engine overheat.

[mapleleaf1773]

Before any of that id check the ofhg and housing for cross coolant contamination. Have you changed it recently?

[saqueme]

Originally Posted by mapleleaf1773

Before any of that id check the ofhg and housing for cross coolant contamination. Have you changed it recently?

I've been checking it pretty frequently, although not recent. The oil looks fine everytime I check

[saqueme]

Originally Posted by Brian86

There just isn't any other way for coolant to get into the exhaust. If you're sure that's what it's doing on startup, it's the head gasket.

Eventually the leak will get bigger and it will start pushing compression into the cooling system. This will result in local overheating initially then coolant getting blown out the release valve. Finally a complete engine overheat.

I've been running like this for 6 months now since I havent seen anything big happen. But you're right, I probably should get it taken care of soon.

[Jerez418]

Originally Posted by saqueme

I've been running like this for 6 months now since I havent seen anything big happen. But you're right, I probably should get it taken care of soon.

Any updates?? I’m getting a sweet smell too on cold start ups but outside of the car. When I go to the exhaust I can’t really tell but sitting in the driver seat it hits me. Then when I roll the window down it somewhat gets stronger. Idk what it could be

Any help would be greatly appreciated