I noticed my coolant was low the other day. I also noticed that wonderful antifreeze smell from the exhaust when unloading groceries today. Now I've got to find the leak, but there is no coolant leaking externally on the engine. Has anyone had to deal with internal engine coolant leaks? Is there some sort of commonality (like 3.1/3.4 GM engine intake gaskets)? I'm going to dig in this weekend but would like to know if there is a common failure point on these engines. Thanks!

 

Coolant leak plus sweet smell from exhaust = time to test for hydrocarbons in exhaust and coolant in oil. Most likely cause is head gasket failure... it is not a common failure unless the engine has been overheated.

 

Low? How low?

Are you sure the smell was coming from the exhaust?

Is the oil milky? Are you getting white smoke exhaust?

Check the reservoir and overflow tubes for cracks/splits. The overflow tube is known to crack/split.

 

There's definitely a sweet smell from the exhaust. The car needed a half gallon last time I put coolant in. The oil is good - no contamination which gives me hope that it's not a head gasket.

 

keep monitoring the coolant consumption - usually these cars don't have issues with coolant - well atleast my experience, and my car is an 04.

 

Common leaks are near the reservoir and the control valve (rear of engine).

 

My two cents: if it's burning coolant out the exhaust, then I believe at best you have a head-gasket leak and at worst you have a warped or cracked head. In addition to checking for coolant mixing in your oil, you can look for compression/combustion gas bubbles forming in the radiator.

 

fixed the above statement- see bolded text

 

I would def be sure that the smell is coming from your exhaust. I smelled coolant for a long time, both in the car with the Cabin air on and outside the car, and thought my head gasket was going byebye. I even found coolant residue in the weirdest places, including the valley of the engine, and the bottom of the crankcase! I then figured out that I had a very small leak in my radiator at the bottom, and when I drove the car, the wind would blow any loose coolant around the engine bay.

Are you finding puddles underneath your car, after it's been parked for a day?

Whatever you do - keep the coolant levels up until you find the problem. If it's a slow leak somewhere, the last thing you want is to find your engine overheating because you have no coolant left.