I would remove the coolant recovery tank and check it for leaks. Repair or replace it. Before you go through the expense of replacing the heater core, try a product made by Zecol called Mendtite. It is one of the few I've used that will seal leaks without plugging the heater core. We used it in racing cars and heavy trucks and equipment with good success. If you google search it you will find it recommended on many forums.



Shake it well. With the engine cold, remove the radiator cap and remove enough coolant from the radiator to put the entire 15 oz contents into it. Move it to the recovery tank. With the radiator cap off, start the engine, shake the bottle well again, pour about 1/2 of it in, shake the remainder, pour it in, install the cap tightly, let the engine run until it gets up to it's 195 degree temperature for several minutes with the heater set at maximum temperature.

 

The heater core being the problem sounds right, except my vents can still blow hot, so no heat loss in the vents.

I found the leak...rather, a spot where antifreeze is running down from. I'll post a picture in a minute, I'm not sure what the part is. The coolant that is leaking is pristine. I've even been able to see the leak with a cold engine minutes after topping off the coolant.

 

Here is the leak in action:


Can someone identify the spot that the leak is coming from?

 

I blew a head gasket on my BMW and I would get white smoke out of the tailpipe. I also had a bad heater core in my FORD and I would get steam & smell on the inside of the truck. I hope it is just the heater core, it will cost you less.

 

WOW ..... I just watched the video(several times).

I have an early 2006 HHR. At that location- I have 4 hoses(2 for AC-on the top) and (2 for heater core-on the bottom).

It looks like you have some type of a drain hole there. My car does NOT have that. I may NOT be seeing it right.

 

My bad ....... yes my car has the same drain hole. It is more on the passenger side of the car. The work shop manual confirms that is the evaporator drain hose. I don't think that is the cause of your problem.

 

I can't watch the vid on my phone. If pristine means clear water not anti freeze that means your A/C has been running, it runs in defrost mode too.

Is the carpet wet on the passenger side? Do you have more oil today than last week? Can you smell coolant coming out the exhaust pipe while idling? Does a large puddle of water form under the exhaust pipe while idling?

Those question should have been asked by a decent mechanic.

 

I may be off the mark here? but check your radiator cap. Make sure the two rubber rings are not worn down flat. I say always start with the most simplest and work from there. Just because you smell the coolant doesn't meant it is coming from your heater core. wouldn't it be nice if all it was is a $15 fix?
Tim

 

When I put in coolant after letting the engine cool a few days ago, coolant leaked out under the car. To reiterate, minutes after I add coolant to the engine while cold, the spot in the video starts leaking out the coolant that I just put in.

No leaks anywhere else. No coolant in the passenger floorboard. But a very strong smell coming from the vents.

 

If the evaporator drain hose isn't the problem, how is coolant leaking out from there?