2008 Impala LTZ developing Anti-Freeze smell

[Earlyboomer]

I bought this 08 Impala LTZ with 3.9 liter engine with 40,100 miles and have put about 500 miles on it. It is developing more of an anti-freeze smell the more I drive it. I have a garage and the enclosed garage makes it more noticeable.

I have added about a pint of 50/50 antifreeze mixture a few times so far. I suspect that Bar's stop leak was used in it before I got it.

I am wondering if this could be another intake gaskets or maybe head gaskets issue with this particular engine. I have noticed with these 60 degree engines, (referring to the angle between the cylinder banks), that the engineers are working pretty close on everything and I would suppose on gasket surface areas also.

Does anyone know the history on these 3.9 liter engines with these issue?
The engine runs smooth and is very responsive and the only other issue is that the electronic dash goes dead for a second or two at a time, which I am going to keep an eye on also.

I usually do most of all my work, but cars today are a lot different and the dealership where I bought it seems reputable so I let them talk me into buying the service policy they are affiliated with. (Usually I am against these service policies because of too many stories I have heard.) I probably will check with the dealer on this, but I like to be informed before hand.

The engine is pretty clean so not much can be seen visually yet, but it is tough to see anything with as tight as everything is in an engine bay today, but I am going to power wash it anyhow, because I do see a few "dirty areas" where some kind of fluid has found its way to. Maybe washing will help find something.

[MT-2500]

If you can smell it it has a leak.
But small leaks are some times hard to find.
Is smell inside or outside?

They make a leak dye fluid for coolant for finding small leaks.
One main thing to watch is the engine oil for coolant in it.
The leak dye will how coolant in the oil.
Also small leaks one engine and rad.

Pressure test it and ckeck coolant system cold and warm and hot.
And watch for leak on underside of everything.

[Earlyboomer]

Thanks for the reply. The smell doesn't seem to be inside, I already checked to see if the heater core might be leaking. The dye is a good idea, I will do that. The oil seems pretty clean but I am going to start using Mobil 1, so before I do that, I will try the dye.

It does smell like the anti-freeze is getting into the intake and being burned. It has that sweet burned smell, unlike the smell of anti-freeze in the bottle. If the engine hasn't been run, the smell is not there.I will report what I find.

I see posts on intake gasket problems with various Impala engines, the 3.4L for one, and a mechanic showed me a plastic intake from a GM V6 where a coolant passage through a boss type protrusion on the underside got eroded by the coolant flow to the point where it no longer sealed. He said he has found more than a couple of these. My 3.9L has a metal intake but it still could have gasket problems which the dye could help me find. (The engine runs very smooth so the fuel/air passages must be sealed.) Getting it pressure tested is a must idea also.

[magnetman]

Isn't it under warranty? Take it to the dealer and let them find it!

[MT-2500]

Yes dye test is best for hard to find leaks
Give it the dye test and see what it shows.
If a intake leak it usually leaks on the outside or into engine oil.
Always watch engine oil and put the dye test light on engine oil.

Pressure test the system cold and warm and hot and watch for leaks.
Let us knownhow it goes.
Good Luck