yoyoguy2

SO... My car was garaged for the winter, and i finally (yes, i know, it's halfway through summer) got it on the road for more than 5 minutes today. while it had been sitting, my father (whose garage stores it) noted one day that a puddle was on the floor, of what he suspected was power steering fluid. as the car has a manual rack, i discounted that, and guessed it to be coolant, which i confirmed by finding the reservoir somewhat low, but not empty.

So today before starting it up i added coolant, and fired her up, then looked on the ground for leaks. i had guessed that a hose/clamp somewhere had given out over the winter, and i'd be able to spot a drop on the ground. no dice. car seems to not be leaking, runs fine, doesn't overheat, coolant level stable after idling for 15 minutes. so off i go.

45 minutes into drive i stop for gas, and check coolant. a little low, so i fill it up, no signs of leaking, so i guessed it was just some more air coming out of the system or something.

anotther 45 minutes of driving, park at friend's house. check coolant, it's a little low, so i throw some more it, but as soon as i do the after run pump kicks on, and coolant literally overflows out of the tank. s#&t. so i wait a sec, put the cap back on, and leave it be.

4-5 hours later, come out of the house, check the tank. EMPTY. so. can't tell if it's on the ground, i parked on the grass, I fill it up, and drive home, wondering what's up. notice white smoke coming from exhaust, somewhat copious, but does not smell like coolant.

1.5 hour drive home, arrive in the driveway, coolant at same level as before, no noticable loss. huh. let it sit for half an hour, check again... still same level, maybe slight loss? hard to say. move car into the garage.

2 hours or so later, tank appears empty again. no puddle on ground at all. noticable pressure in tank when cap is removed (in all occasions... i think)



so, what's the analysis? i'm thinking: somehow, coolant is leaking into the engine/combustion chamber while the car is sitting, but not when it's running. this would keep it off the ground, cause white smoke on startup, etc. problems with this are 1) that's a lot to be getting into a cylinder, seems like if it was half full it wouldn't start, would hydrolock, something 2)why not while driving? 3) if it were this much, some woudl be in the oil. other ideas are something with the turbo after run pump, which would therefore not be in play while driving. car does not overheat. no coolant in oil, or oil in coolant, that i can see. your help or suggestions would be much appreicated.

Techno Duck

Thick white smoke from the exhaust means its burning off in the cylinder, which possibily means a blown head gasket. The exhaust will have a sweet smell to it. Check your dipstick to see if the oil is still the right color.. if its a milky white milkshake kinda color, your coolant mixed with the oil and that can mean a possible blown head gasket. Oil in the coolant tank usually means a leaking oil cooler i believe. But i think you would have noticed that if you kept refilling.

Edit - I am not an expert in the area, but i would say the problem is not occuring when driving because the pressure in the cylinder is pushing the coolant back out of the cylinders, when the car is stopped..there is no compression in the cylinder so its collecting.

As another check, let the car sit until you get noticable loss of coolant, then pull all 4 spark plugs and peak into the cylinder with a flash light.

GOSANE

Just make sure your oil level isn't going up.

That happened to me one time........the old chocolate milk for oil story.

GOSANE

yoyoguy2

yeah, oil level seems to be constant and not milky... i'm going to pull the spark plugs tomorrow morning and see if i can find any signs of coolant in the cylinders... if not then i'm at a loss really, have to come up with some more tests

Mark-87-951

Is it hard to start? I had problems with starting and white smoke right after start. Before it got that bad I had the mysteriously disappearing coolant. Blown headgasket. On mine the 4th cylinder fire ring had distorted substantially.

Mike C.

You might try bleeding the cooling system. Depending on where it leaked out, you might have an air bubble that is getting smaller as you run the car (although if it had that much air I would have expected temp problems). Also, were you able to inspect the leaked fluid (that your Dad mentioned) to verify what it was? It should be pretty easy to tell if it was oil or coolant.

cjeckert

I had the same series of things happen and it just turned out to be a bad radiator cap that wasnt sealing properly

hosrom_951

White smoke from the exhaust means that coolant is entering the combustion chamber, a leaking head gasket.

Coolant always low, without leaks is backing me up

A leak down test would confirm th gasket.....but it is not all that bad, i replaced the gasket on my 951 a few weeks back. 90% labour, 10% parts and an endless list of "while you are in there" which is sure to burn a hole in the wallet (such as oil cooler seals, cam seals, valve guides, valve seats, springs and so on).......

If you are going for the gasket itself, make sure you replace at least three items, which are the headgasket, cam tower gasket and valve stem seals.....that's the minimum.

35thSLP

I had the same thing happen earlier this year, disappearing coolant that is. No white smoke. Ended up being my oil cooler seals.

SD Porsche Fan

I had a leaky hose that goes from the water pump to the hard line that feeds the heater core. That is pretty close to the exhaust manifold and the coolant can "burn off'. It is a pretty strong smell though. You'd probably notice that and smoke from under the hood.