Mechanics--Ford Fusion/Mercury Milan occasional coolant smell?

[Matt Meiser]

Still under warranty so we are taking it in tomorrow for the dealer to check out, but I thought I'd ask here too in case they have trouble tracking down what, if anything is wrong. Google didn't really turn up anything. We have a 2011 Milan with the 4 cylinder. It has the automatic dual-zone climate control if it matters. The last few weeks I've occasionally gotten a whiff of coolant inside or under the hood. The other day it was a pretty good inside the car on start-up but went away almost right away. That day LOML had gotten home from maybe 15 miles of driving, and it was warm and sunny so AC was on. We left about an hour later which is when I noticed. Didn't smell it again that day during maybe 25 miles of driving. Drove it quite a bit yesterday with the heat on and there was no smell inside or out. I'm not sure if the smell is getting inside via the cabin air filter or, worse, if there's a heater core leak. Heater core doesn't really make sense though as there's no sign of fogging the windows and it comes and goes maybe even opposite of heat use. There's never a puddle of coolant under the car, the AC condensate that drains doesn't have any odor, and it doesn't seem to be using any coolant. I've also never walked into the garage and noticed a smell after its been sitting in the closed-up garage for a bit after we get home.

[Jeff Monson]

Sounds like something leaking on the engine and burning off, that would explain the smell and no puddles. Maybe a water pump, or it could even be a radiator seam that is seeping. A pressure test and a visual inspection should reveal the suspect.

[Matt Meiser]

Thanks Jeff. I'm hoping its something relatively simpler like that. We've only got about 5K miles left on the bumper-bumper warranty so I want to make sure they track it down before that's up in case its something outside the 6/60 powertrain warranty. I'd hate to see them have to do a heater core on it which I assume is a major job but I'd rather Ford pay for that than me!

[Jason Roehl]

Overflow bottle empty? If there's no coolant in the overflow reservoir, sometimes you'll get some steam out of that bottle. If there's coolant in there, the steam comes in the bottom and is condensed into liquid itself by the cooler liquid coolant. You may have a bad radiator cap if that's the case (or a cracked overflow bottle or hose).

I once had an ornery leak that I couldn't find--I couldn't ever find evidence of it other than I had to periodically add coolant. It turned out to be the short, dog-legged bypass hose on the thermostat. The leak was inside the elbow, and was small enough that it wouldn't leak when cold, only once the coolant started to warm up and the rubber hose would soften. Of course, once the coolant was up to temp and the thermostat opened, nothing would flow through that bypass hose. I only found the leak when I happened to pop the hood when the truck wasn't quite warmed up and I saw the coolant squirting out that pinhole.

[Matt Meiser]

This has one of those newer-style pressurized plastic tanks. I haven't remembered to check it when cold (fill level is only indicated "cold") but there's coolant in it and always at the same point after the last few weeks. I'm not even sure it has a traditional radiator cap now that you mention it.

[ray hampton]

the wife own a chevy X NUMBER OF YEARS AGO with a leak that we could not find until I happen to open the hood when the sun was at the right angle to shine on a leaking hose [4 " long], working on cars are simply when the sun are out compare to no sun

[Chuck Wintle]

Still under warranty so we are taking it in tomorrow for the dealer to check out, but I thought I'd ask here too in case they have trouble tracking down what, if anything is wrong. Google didn't really turn up anything. We have a 2011 Milan with the 4 cylinder. It has the automatic dual-zone climate control if it matters. The last few weeks I've occasionally gotten a whiff of coolant inside or under the hood. The other day it was a pretty good inside the car on start-up but went away almost right away. That day LOML had gotten home from maybe 15 miles of driving, and it was warm and sunny so AC was on. We left about an hour later which is when I noticed. Didn't smell it again that day during maybe 25 miles of driving. Drove it quite a bit yesterday with the heat on and there was no smell inside or out. I'm not sure if the smell is getting inside via the cabin air filter or, worse, if there's a heater core leak. Heater core doesn't really make sense though as there's no sign of fogging the windows and it comes and goes maybe even opposite of heat use. There's never a puddle of coolant under the car, the AC condensate that drains doesn't have any odor, and it doesn't seem to be using any coolant. I've also never walked into the garage and noticed a smell after its been sitting in the closed-up garage for a bit after we get home.
did you ever notice any drips on the driveway or in the garage? Does it happen all the time, only when the motor is cold or when is is hot or both?

[Brian Tymchak]

this would be a real long shot, but I had a similar issue a long time ago (mid 80s). My mother was smelling what she described as antifreeze in her car. Just occasionally. So I checked all the usual culprits: heater core for leaks, any leak at all under the hood, etc, couldn't find anything. One day I was driving her car, and used the windshield wipers and fluid to clean the windshield. Later, like maybe 20 minutes, I got a wiff of alcohol. It took a while, but I found a bad seal at the bottom of the windshield where the catch basin met the firewall. The glue had bubbled when installed and apparently with time, those bubbles had broken down and started allowing fluid to trickle down inside the firewall. Broke out the bubbles some more and sealed it all up with some silicon-based caulk and all was good.

[Matt Meiser]

Its at the dealer now so we'll see what they say. Hopefully something simple so they can just fix it today.

[Matt Meiser]

Well, car is back home. They visually checked it over, couldn't smell anything, and did a pressure test and couldn't find anything. Service advisor says its documented now though so if it does turn out to be something they should be able to get Ford to back us up on it even if we are out of warranty. I'm going to change the cabin air filter on the off chance its picked up something that's tricking my nose. Probably past time anyway. Got to thinking that this has really just started since AC season which is when it would be drawing outside air.