[aidanricha]

Just bought a 2003 9-3 SE Convertible, 99,733 miles. Has a slight oil leak on left side of engine. When driving it home, it did perfectly fine for the 20 min drive. About 3 mins after I parked it and turned it off, I noticed white smoke coming from where the coolant reservoir is. Then I watched coolant spew out from under the hood and made a complete mess under the car. Figured the wrong coolant/oil was used previously. So I did an oil change with Mobil-1 5w-40 full syn + K&N filter, and did a coolant “flush” (removed lower radiator hose, let drain, then refilled with dexcool 50/50 mix). Went for a test drive, was fine for 10 mins, then I saw more white smoke and coolant spewing again. All the while the coolant temp gauge stayed at normal temp, right in the middle, and engine ran just fine. After some research seems like bad head gasket.. just need some help.

 

[EdT]

What did the old oil look like? And the old coolant?

I assume that the second time this happened, you were still driving?

But yes, sounds like a head gasket. I guess you could do a compression test. That may or may not show lower compression in the bad cylinder(s),

 

[aidanricha]

What did the old oil look like? And the old coolant?

I assume that the second time this happened, you were still driving?

But yes, sounds like a head gasket. I guess you could do a compression test. That may or may not show lower compression in the bad cylinder(s),

Oil was definitely dark, was overdue. Couldn’t entirely tell the color of coolant but it was darker and some other areas where it leaked it was green?

 

[EdT]

Coolant in oil looks like chocolate milkshake. Doesn't sound like what you had.

Oil in coolant would produce globs of dark stuff I guess. (Luckily, I have not had to fix a Saab head gasket.)

 

[aidanricha]

Coolant in oil looks like chocolate milkshake. Doesn't sound like what you had.

Oil in coolant would produce globs of dark stuff I guess. (Luckily, I have not had to fix a Saab head gasket.)

Yeah, there definitely was no coolant in oil and I did not notice any globs in the coolant.

 

[jvanabra]

Could be anything from a coolant leak ingesting air that expands under heat, a bad coolant reservoir cap, or a failed head gasket. Rent a block test kit from Autozone, etc. It will help point you in the right direction.

 

[davide c]

Refill (adequately) the Exp tank . Leave lid off, then run the motor. (car stationary).
Under rev up there will be a wee bubble fountain in the Expansion tank ..IF.. the HG is leaking. Watch for this evidence.
Coolant rarely gets into the Oil from a HG leak (unless a disasterous failure) as oil pressure is Much higher than water.

 

[jvanabra]

That depends on where the failure is, doesn't it? The head gasket can fail between water and oil, oil and water, two combustion chambers, combustion chamber and water, or even, rarely, combustion chamber and oil. There isn't a rule to how the gasket will fail.

 

[Saaberachi]

Make sure u know what coolant is in there too. Its not advised to mix dexcool with green.

 

[fast_mag]

Where does the water / smoke come out from? The coolant tank? If so it may be cracked or a bad coolant reservoir cap (been through both). When pressure builds up during after-boil it comes out through the leak. If the leak is above the coolant level you won't generally see it while the engine is running.

 

[Mirabeau]

From what you're describing, if it were the head gasket you should've/would've noticed some amount of cross-contamination in either the coolant or oil you drained for it to overpressurise the cooling system to that extent. Regardless, the leak had to come from somewhere and you need to find out where.

You said it appeared around the coolant reservoir the first time; could you see exactly where; was it around the cap or the hose underneath?

The wrong spec oil or even a cooling system filled with tap water shouldn't cause a properly functioning system to overpressurise. And if your temp gauge is accurate and didn't move higher than what is normal, you can pretty much rule out a faulty thermostat.

Firstly, pressure test the cooling system when it's cold and I suspect you'll locate it pretty quickly. The only thing you won't be able to test during that is the cap itself. If nothing leaks, then top it up, put the cap back on and run it with the bonnet up. Get it relatively warm the first time (not hot) and shut it off so you get the pressure spike and watch (from a safe distance). If still nothing, start it gain and repeat, getting it hotter each time until it starts to leak.

And lastly, it doesn't sound like your problem, but are you sure it didn't come from around the back area of the engine where the (notorious) heater bypass valve is? Did you have your A/C on when this happened?
I've only ever had them catastrophically fail whilst driving, but I have replaced a few weeping ones on other cars and it's a known area of cooling system leaks and is conveniently positioned above the exhaust, so a small leak can produce a lot of steam. Again, it doesn't sound like your problem, but something to keep in mind at least.