dunno the issue is yet...billows of "steam" from the engine compartment of a 2005 wrx. any guesses before we know for certain?

 

more details please

 

really...that's all i can give you - no other symptoms!

 

He means

Mileage, mods, Maintence, etc. if it has 40 miles and is bone stock it will probably be a different issue than 150k with parts to put down 500whp

Yes very exaggerated... Getting my point across

 

Couple things. Any distinct smell to the steam? Are you sure it's steam and not smoke?
Going off the assumption if steam, the coolant line from the turbo may be leaking onto the up/down pipes. You may have too much coolant in the system which is getting barfed out under load. You may have a loose hose. Check your upper and lower for leakage stains. Remember we have a bit more plumbing than a lot of cars. Do you only notice it sometimes?

Has any work been done to the car at all recently? Do you notice any temp gauge fluctuation at all? If it billows as you said, can you pop the hood and take a video so we can try to source it?

Otherwise, if it was more like a one time occurrence of smoke/steam you may have something resting on your down pipe such as the AC drainage tube. Either that or you may have gone into some water which is cooking off your down pipe. That wouldn't explain long term billowing though.

 

OK...under 100K, stock, well maintained

 

May have a pinhole leak in the radiator. Usually happens at the top. Check that out because if it lets go on the freeway you might cook rod and main bearings if you run hot enough.

 

That would be my guess too. My radiator went at 100K as well. Have you done the timing belt yet since it is due at 105K? Might set aside additional funds and have it done at the same time.

The OE upper hose on mine also failed, which likely contributed to the failure of the radiator. The hoses swell and crack at that sort of mileage as well. I just recently bought my FXT and the upper hose was starting to do the same thing at 119K so I replaced them, radiator fine.

 

i peered best i could around the radiator once the steam cleared. the radiator and adjacent parts were drenched and a there was generous pool of coolant at the bottom, so i just shut it down and had it towed. so difficult to get a rental car close to EOB. those guys take going home on time serious.

i don't usually carry a fire extinguisher in the car, but i will get one soon!

 

it was a hose!

 

Upper or lower? Upper nicked by pulleys, or just an old OEM swell and burst?

 

upper hose - here you see where the fan blade rubbed the hose, creating a concave abrasion. the hose is very supple, unlike the replacement hose.