Mechanic Help needed

[WallsGa]

Wife’s car, 2015 Kia Sorento, 80k miles:

Noticed a smell of burning coolant a week ago. It was leaking coolant from the cap. Repair shop checked it out. (Five Star Auto in Athens, they’re pretty good)

Pressure test - no issues. Water pump - no issues. Thermostat - no issues, but changed it anyway. Nothing they can find. No radiator leaks anywhere.

It overheated once a few days ago when driving it. Just the once though.

No noticeable leaks or burning smell for the past few days. Until today. Wife drove it home and the smell of leaky burning coolant returned. Engine light came on today when wife cranked it up to come home.

Any ideas of what could be causing it? Looking for ideas before I take it to the dealership for the $200 diagnostic test. What better place for master mechanic advice than ODT!

 

[Dallasdave]

I thought those had a 5 year 100k warranty

 

[Dallasdave]

Might be at the intake burning off on the exhaust manifold. Any antifreeze in the oil

 

[NewLeaf]

heater core?? "no visible leak" hope it's not head trouble

 

[jeep78]

Put a new cap on, cheap and they do go bad.

Get one of the test kits to check for exhaust gas in coolant. It is a chemical test for blown head gasket.

Check coolant in radiator and overflow bottle every day before first use until you find the problem.

 

[harrycalahan]

If the smell you’re smelling is the coolant actually burning off a hot surface, then you’ve probably got a plastic component thats leaking under pressure and when at operating temp. When cold or less than operating temp/pressure, it may not leak when leak tested. If it was the heater core leaking enough to cause it to over heat in one trip, Id think you’d be sick from the smell in the car. Ive had leaky cores that burned my eyes it was so strong. Bet its a plastic manifold, thermostat housing, radiator tank etc.

 

[MRM]

I'd have the code pulled first.
The old school caps have a rated pressure and it would vent to the overflow above that pressure. The spring would get weak or malfunction and vent below the rated pressure.
I don't know about the new ones that only have a cap on the overflow.

If you like the five star guys, take it back and see what they say.

That thing probably has electric fans and they could be malfunctioning. I would want it diagnosed instead of just throwing parts at it.

 

[41mag]

Radiators are made of plastic, they will seep when hot. Usually in the corners. Small crack, may not show up until operating temp.
Just my experience

 

[dcline9163]

Put a new cap on, cheap and they do go bad.

Get one of the test kits to check for exhaust gas in coolant. It is a chemical test for blown head gasket.

Check coolant in radiator and overflow bottle every day before first use until you find the problem.

This, it happened to my daughter's car once.

 

[WallsGa]

They replaced the cap, checked the heads, and did a pressure test. No leaks. No smell inside the car, just intermittently outside.