Subaru Outback Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
13 Posts
Discussion Starter #1
Hello,

I have a 2012 Outback 2.5 Premium that I purchased new last February. It just turned over 12,000 miles today. Here's what has been happening lately. Every time I drive the car for any length of time, to the point of warming up the engine, I smell coolant, especially when I stop and turn the car off. It seems to dissipate rapidly, but the odor is strong. I have no discernible leaks--nothing on the garage floor. I can't figure this one out, but I certainly don't think it's normal.

Thanks for any ideas, feedback, suggestions, etc.
 

·
Registered
Joined
·
666 Posts
randwulf,

Deja Vu. I bought a new OBW LTD in 2004 and in very short order (about the same mileage as you) I experienced the exact same symptoms. Took it back to the dealership and they found small amounts of coolant leaking from the heads externally. Nothing was visible from above, but they found it when it was on a hoist. They made an appointment for the next week for me and changed both head gaskets under warranty. The problem never occurred again, and I put 269 000 km on the car when I traded it for my present 07 OBW LTD.

You may have the same issue, or a small leak somewhere in a rad /heater hose or the rad itself. You need to get the car back to the dealership. Good Luck!
 

·
Registered
Joined
·
91 Posts
You are right to be concerned. From my experience any smell of coolant has always been due to a leak, often a fine mist when the system is under pressure. Most notable was the head gasket on my 2000 outback, but had the same smell when a hose sprung a pin hole leak. The big problem was trying to find it, because, as you said, no visible leak on ground. Try tightening all coolant hose clamps (radiator and heater hoses) and check carefully around the engine and heater with a flashlight and mirror for anything looking antifreeze greenish.

Whatever it is, it should be covered under warranty.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #4
Thanks, guys. I appreciate the responses. I was afraid there was a problem. I'll look for leaks tomorrow. I may be off to the dealer later this week. What a hassle.
 

·
Registered
Joined
·
20 Posts
It could be something as simple and inexpensive as the radiator cap. They're supposed to seal from the factory, and many of them do, but sometimes not for very long, and not at the pressure they're supposed to be rated for. When you turn the engine off particularly after running it relatively hard, it is going to heat soak and the pressure in the cooling system will actually rise: there's nothing turning the water pump, there's no air flowing through the engine compartment, and the exhaust manifold(s) are still HOT, as are the cylinder heads, particularly around the exhaust valves. Remember, too that a lot of new cars are designed to meet very stringent emission requirements - which means those catalytic converters are CLOSE to the engine compartment and exhaust manifolds for fast "light off" and they get *very* hot. The result is many, many BTUs of thermal energy that have to go somewhere when you turn off the car. The first place they try to go is the cooling system.

If the cap is marginal or defective you can smell it, because the coolant boils off and escapes past the seal.

Early turbocharged Audi Quattros had an "after run cooling pump" that actually had its own thermostat and switched on when the engine was turned off, to pump the coolant around and keep it from boiling because of the latent heat from the turbocharger and exhaust manifold soaking back into the engine block. Some of those turbos and manifolds would get so hot that you could open the hood in a dark garage and see them glowing dull to bright orange, particularly if you had just run the car hard. About 20-30 seconds after you'd switch off, you'd hear the after-run coolant pump start up, and it would stay on for several minutes in some cases. In extreme cases even the electric cooling fans would continue to run during the whole time, and in fact they would switch to higher speeds to dissipate the heat. So you'd shut the car off and 1 minute later it was howling in the garage like it was still running. This is on a 100% stock, "from-the-factory" car. Glowing exhaust manifolds and turbocharger and I've seen it many times.

If the rest of the cooling system wasn't sealed, particularly the radiator/reservoir cap, you could smell it **right away**. You could hear it boil. The reservoir cap was a pain, and sometimes the reservoir itself *cracked* from the pressure and temperature of the coolant. In fact that was a major headache on the early Turbo cars: cracks in the coolant reservoir, even with the after-run pump working perfectly. The post-shutdown heat soak temperatures and pressures were so high sometimes that they just overwhelmed the thick plastic coolant reservoirs themselves, nevermind the caps.

This isn't a turbo car, but a poorly-sealing radiator cap can mimic a much larger problem. So look there first.

Good luck I hope it's something simple and inexpensive like that. It could very well be.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #6
Thanks, Subaru01. I just looked everywhere in the engine compartment for any signs of leakage, and found none. I checked all hose clamps as instructed, and they all seemed OK, too. It's interesting that you mention the radiator cap, because the smell seems to originate near the radiator cap and the reservoir. I hope it is as simple as that.

Thanks again, guys.
 

·
Registered
Joined
·
22,836 Posts
There was a thread discussion just like this back when the Gen 4 first showed up in 2010. My OB and my 2010 Legacy both had a similar smell. The verdict by several posters was the smell being various oils and parts burning off the manufacturing oils. I sort of recall that people were noticing between say 10K and 20K but after that no one was really noticing it.

Also if the coolant level is staying level then clearly you don't have a leak.
 

·
Registered
Joined
·
20 Posts
Thanks, Subaru01. I just looked everywhere in the engine compartment for any signs of leakage, and found none. I checked all hose clamps as instructed, and they all seemed OK, too. It's interesting that you mention the radiator cap, because the smell seems to originate near the radiator cap and the reservoir. I hope it is as simple as that.

Thanks again, guys.
Welcome and also: I'm not sure how the cooling fans are triggered on the 4th Gen Outbacks. My guess is that it's a temperature switch that can run the fan after the car turns off if the coolant gets too hot from a heat soak.

It could be that you have a problem with the switch/mechanism that allows the electric cooling fan to after-run! They're usually cheap too. If the fan is supposed to come on and doesn't, that will lead to higher pressures in the cooling system and then it's plausible that you could get the radiator cap past its pressure limits.

Again, this would happen from time to time on the Audis when the switch that triggered the after-run coolant pump *itself* failed. When all three things failed (thermoswitch, afterrun coolant pump and afterrun fan thermoswitches) you could *count* on a major coolant loss and possibly a blown head gasket after you parked the car after a hard run - and nothing was mechanically wrong with the engine! It simply couldn't take the heat soak without the switches and electrical bits doing their part. It's one of those: "For the want of a nail....the Kingdom was lost!" scenarios and it actually happens.

The switch is probably a little more expensive than the cap but again, it's not a major repair.

Best wishes and let us know what it finally turns out to be. You'll find it. You shouldn't be able to smell coolant like that.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #9
There was a thread discussion just like this back when the Gen 4 first showed up in 2010. My OB and my 2010 Legacy both had a similar smell. The verdict by several posters was the smell being various oils and parts burning off the manufacturing oils. I sort of recall that people were noticing between say 10K and 20K but after that no one was really noticing it.

Also if the coolant level is staying level then clearly you don't have a leak.
I actually had to add coolant last week before taking a trip. I only added a small amount, and I'm keeping a close eye on it. I'll keep the board posted on what I finally figure out.

Thanks again.
 

·
Registered
Joined
·
1 Posts
Hello,

I have a 2012 Outback 2.5 Premium that I purchased new last February. It just turned over 12,000 miles today. Here's what has been happening lately. Every time I drive the car for any length of time, to the point of warming up the engine, I smell coolant, especially when I stop and turn the car off. It seems to dissipate rapidly, but the odor is strong. I have no discernible leaks--nothing on the garage floor. I can't figure this one out, but I certainly don't think it's normal.

Thanks for any ideas, feedback, suggestions, etc.
What was the outcome? My 2012 Subaru Outback (14,000 miles) is VERY low on coolant and am not sure why?
 

·
Registered
Joined
·
13 Posts
Discussion Starter #11
What was the outcome? My 2012 Subaru Outback (14,000 miles) is VERY low on coolant and am not sure why?
No resolution, Dawnelle. Still have the problem and Subaru says nothing's wrong. Don't know that I'd ever buy another Subaru.
 

·
Registered
Joined
·
1 Posts
Fixed and back again

I experienced the same issue except there was noticeable amount of coolant missing from the expansion tank. Every 2 weeks it would be down about 1/2 inch prior to start (cold) and then became progressively worse. It was a crack in the plastic tank on the radiator near the crimp. They are noted for cracking due to poor design. I am back at the leak stage with the coolant smell occasionally creeping in through the vent. Radiator or head gasket...not sure as there is again no other visible sign except the expansion tank. Good luck and hope you have a good dealership to locate it. Mine took 9 trips and they told me it was normal to lose coolant. Ha!
 
1 - 12 of 12 Posts
About this Discussion
11 Replies
7 Participants
scooter518
Subaru Outback Forums
Welcome to the Subaru Outback Owners Forum, we have tons of information about your Subaru Outback, from a Subaru Outback Wiki to customer reviews.
Full Forum Listing
Top