UH OH, Big overheating prblms!!!
Thread Starter
Burning Brakes
Joined: Aug 2001
Posts: 1,146
Likes: 9
From: Troy Ohio
UH OH, Big overheating prblms!!!
Well, first off Iv'e learned that when the coolant low light comes on in my car, pull it over now!! I'm on the highway, light comes on and temp immediately starts climbing fast. Before I could get it off the exit I'm pushing 250+. I let it cool down a little and pull the cap. Lots of brown coolant comes gushingout. Overflow is full...Refill the radiator, gun it and see coolant flowing strong through the radiator, this makes me assume thermostat and water pump are ok? Temps come down so I get back on highway for 10 mile drive home. Low coolant light on again sparadically. Get it home and let it sit 15 min and start back up and a huge cloud of white smoke!!! Once it clears I'm smelling gas real strong, like it running rich. Funny thing is I dont smell any antifreeze in the exhaust. What to look at next? Theres no crap in front of radiatior, And I'm at a loss. Thanks in advance for any help.
Heel & Toe
Joined: May 2006
Posts: 15
Likes: 0
From: Bainbridge Ga
Originally Posted by Tom 35th anniversary
Get it home and let it sit 15 min and start back up and a huge cloud of white smoke!!! Once it clears I'm smelling gas real strong, like it running rich. Funny thing is I dont smell any antifreeze in the exhaust. What to look at next? Theres no crap in front of radiatior, And I'm at a loss. Thanks in advance for any help.
Team Owner
Joined: Jul 2003
Posts: 24,650
Likes: 8
Bad news dude...
250 is the upper limit of the system...If it hit 250, and then puffed white smoke, you have, at the very least a blown gasket, possibly warped heads.
I got lucky on my 85, with the cast heads, I hit 255, with no damage...
Drain the radiator, drain the oil. You see any sludge come out of the radiator that looks like oil, or see any water or "cocoa" in the oil, you'll need to pull the plugs and find out which side is damaged.
Id suggest NOT running it until you know more as to why it puffed white smoke.
You know one thing for sure. You have coolant leaving the system somewhere, if you dont see any leaks, and dont smell it inside the cabin, it must be going into the cylinders...
250 is the upper limit of the system...If it hit 250, and then puffed white smoke, you have, at the very least a blown gasket, possibly warped heads.
I got lucky on my 85, with the cast heads, I hit 255, with no damage...
Drain the radiator, drain the oil. You see any sludge come out of the radiator that looks like oil, or see any water or "cocoa" in the oil, you'll need to pull the plugs and find out which side is damaged.
Id suggest NOT running it until you know more as to why it puffed white smoke.
You know one thing for sure. You have coolant leaving the system somewhere, if you dont see any leaks, and dont smell it inside the cabin, it must be going into the cylinders...
Team Owner
Joined: Sep 2001
Posts: 62,153
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Symptoms are similar to a blown head gasket.
I would verify that the thermostat is opening at 195 as it should if its stock. Watch the coolant temps when it reaches that, it should hold for a few moments.
Pressure test the radiator, and you can have them do a check for hydrocarbons. If those checks turn out fine then you may need to just flush out the system.
But if it starts puffing out white smoke, and it wasnt cold the night before, then you have a head gasket problem.
I would verify that the thermostat is opening at 195 as it should if its stock. Watch the coolant temps when it reaches that, it should hold for a few moments.
Pressure test the radiator, and you can have them do a check for hydrocarbons. If those checks turn out fine then you may need to just flush out the system.
But if it starts puffing out white smoke, and it wasnt cold the night before, then you have a head gasket problem.
Burning Brakes
Joined: May 2006
Posts: 1,097
Likes: 2
From: Richfield Utah
White smoke out of the tailpipes - Coolant. Black smoke out of the tailpipes - Engine Running Rich. Blue smoke out of the tailpipes - Oil. This one does sound like a cylinder head gasket, or warped head. Get that pressure check that vader suggested. As a matter of fact I'm just about to put on my new waterpump. I have got to remember to pressure check that cooling system (88 Coupe) before I have it all together. Best of luck... 
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Thread Starter
Burning Brakes
Joined: Aug 2001
Posts: 1,146
Likes: 9
From: Troy Ohio
Thanks guys...
I checked the oil....looks like oil, no water. The radiator fluid looked rusty brown..didnt see any oil in it either but, the coolant usually looked mostly green before this episode. I'll check the other stuff when I get some time. Thanks guys for your responses.
Team Owner
Joined: Sep 2003
Posts: 88,393
Likes: 2
From: eville in
Originally Posted by Tom 35th anniversary
I checked the oil....looks like oil, no water. The radiator fluid looked rusty brown..didnt see any oil in it either but, the coolant usually looked mostly green before this episode. I'll check the other stuff when I get some time. Thanks guys for your responses.