[arb99a]

I was driving the other day and noticed the AC started blowing warm air and then the temperature gauge was near the red zone. After I stopped driving, I noticed the coolant tank was low. I hadn’t noticed any leaks before, but it was low so I added more antifreeze assuming that was the issue. The next day, I’m driving again and the temperature keeps getting hotter and the AC starts blowing warm air...this time the temp gauge is topped out. I get home quickly and turn off the car and then steam and antifreeze start spewing out all over. The fans are on and working when I pop the hood. So I know it’s not a coolant level issue and it’s not a fan issue. I’m dreading it being a head gasket issue. What else could be the culprit? I’m not a very skilled mechanic, but I’d do easy to easy/moderate level work to save thousands of dollars.

 

[TankTak]

Sounds like your thermostat failed to open causing overheating. anytime you are driving and see your temps start to rise its always good practice to turn on the heater full blast if you must keep driving. But doing so can and will possibly cause your head gasket to fail.

 

[Mike Brennan]

If he spiked the temp gage he may have already killed the top end.

Why would you drive a car into the red zone on the gauge.

 

[hoppysport]

I actually carry an old DIC, a Crank Position Sensor and a Thermostat in the trunk of my 98,000 mile 08 9-5. I last changed my thermostat at 65,000 miles. Changed the DIC as 62,000 miles. Never changed the CPS.

 

[unclemiltie]

IT's hard to say what might have happened, thermostat stuck (although they are designed to fail "open"), some other obstruction or something else.

But driving while the coolant was in the "red" is a bad idea on any vehicle with an aluminum head like the 9-5.

What I'd do if I were you is to pull the thermostat out and use a set of tin ships to cut the middle part out of it and put it back. that will allow you to seal up the system without spending any money, just your time.

Then fill the cooling system with distilled water, it's cheap from the grocery store. Distilled is important because all of the minerals are out of the water. you're not going to leave it in long so why waste anti-freeze.

now run the car and see what happens. Don't go far but do "jump on it" and get the turbo boosting. What happens?

you can also go to the auto parts store and buy a test kit to test for combustion byproducts in the coolant. Get one, test the water once you've driven a few miles (assuming it doesn't overheat again)

Then report back what you find. you may have gotten lucky and not destroyed the head gasket and maybe warped the head. Let's hope so!

 

[unclemiltie]

Sounds like your thermostat failed to open causing overheating. anytime you are driving and see your temps start to rise its always good practice to turn on the heater full blast if you must keep driving. But doing so can and will possibly cause your head gasket to fail.

Any time you are driving and see your temps getting into the red zone you should pull to the side of the road and turn the car off. Anything more and you risk an expensive repair.

 

[Mike Brennan]

Actually distilled water should never go into radiator. Pure water is an acid. Water with minerals neutralize the acid.
Sounds stupid if you've never heard that before but it's the truth.

 

[andybisnut]

Actually distilled water should never go into radiator. Pure water is an acid. Water with minerals neutralize the acid.
Sounds stupid if you've never heard that before but it's the truth.

Are you sure about this? Distilled water should have a pH near 7, which is neutral. I've always thought distilled water was neutral, or very close to it.

 

[shaggy]

Freshly distilled water is neutral but once oxygen is absorbed it becomes slightly acidic

https://sciencing.com/ph-distilled-water-4623914.html

S

 

[unclemiltie]

but there is likely enough anti-freeze left in the system that it won't matter. at least for a short term fix. If you're going to leave it in there for weeks, not so much.