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Car is spewing coolant out of exhaust

4941 Views 14 Replies 8 Participants Last post by  Legacy
On the way to work this morning, getting on the freeway, boost was around 10psi, casually accelerating to 70mph. I heard a slight thunk, then I look to my side and there is a CLOUD of exhaust, and it stayed there, but its not exhaust, its coolant, quickly my coolant hud said I was low, I pulled over, and under the hood it looks like an explosion of coolant happened near Cylinder 1. But I pulled the dip stick and there is no coolant in the oil. Anyone have ideas of what this could be? Water Pump? Turbo? I am at work now and the car is being towed home, I will not get a better look till then, but this is the just of it and any help would be appreciated.
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My first thought was head gasket but then(see below)\/

My bad I re read the post and I misunderstood from the way you wrote it I thought there was smoke coming out of the exhaust. so yeah could be anything lol. Turbo collant hose/lines..waterpump seems more likely though since you stated around #1 :shrug:
wonder if the turbo coolent line has a hole in it call me when you get off
number one cylinder is near the water pump right?(i always get it mixed up) could be your water pump or maybe your hose has a tear in it down near the coolant hose mates with the block? thats what id check.
Well to help clear things up because my OP seemed confusing, there was an assload of smoke coming out of the exhaust, behind me people litereally had a face full of smoke, it produced a huge cloud behind my car. But when I pulled over and checked, there was a ton of coolant (actual liquid) coming out the exhaust. But since the coolant isnt in the oil, that suggests a cracked head, right?
that sounds backwards, wouldn't a cracked head result in fluids mixing? whereas a damaged head gasket would cause the symptoms you're getting :shrug: or maybe i've got it backwards :)
Sounds like Water Pump Or HeadGasket and or a crack head.
If coolant was running out of your exhaust, it could be a leaking headgasket even though you didn't see any coolant in the oil. When my headgasket went bad it was just letting coolant leak into the cylinder nearest the distributor, though I never saw it dripping from my exhaust.

Of course, the sound you heard could be a number of things. If something mechanically went bad in the head and made it crack, it could be a lot more severe than just a headgasket.
Well got home from work just now, but I have alot of paperwork I need to finish, I might not get a chance to check it out, I will look later tonight hopefully. Someone suggested blown head gasket and the surge from the cooling system blew the coolant resvoir cap off or a hose thats why there is an explosion of water inside. Will check for cracks on the block and that, I hope its just a head gasket. Anyway thanks for all the advice, I know what I need to look for I just need to get around to doing it.
Grab a compression tester, that will tell you if the headgasket is gone. Blew one doing 70 MPH, wow what a cloud.... Also blew the coolant hose for the turbo, yes another cloud.

Does the car idle fine? If it is coming out of the exhaust pipe, you have a head gasket job ahead of you. Can be done in a day if you do it smart.

Now that said don't use a cheap gasket. Fel-Pro, please.

Do some more diags and get closer to real root cause. This will give you better direction......

Well I got a chance to drain the coolant and oil.

Coolant had exhaust fumes in it, so obviously the head gasket is gone and/or cracked head.

Oil seemed fine, I dont know what oil is consistant with if it has antifreeze in it, can anyone give me ideas of what oil is like with antifreeze in it?

It almost turns a white/cream color and is very watery/chunky.
RockAuto Parts Catalog

Is that the good kind?

And since I am going to need to rip apart everything should I get a whole head kit and replace it all?
You'll definitely want the full kit, it'll have gaskets for the intake manifold, the distributor housing, water temp housing, valve cover, etc. And yeah, I've heard good things about Felpro or you can get a Mazda OEM head gasket. The kit will also have new valve seals which would be a good idea to replace.

If your head isn't cracked, you might consider getting new springs, keepers, maybe even new valves depending on how much you're willing to spend. I did all that with mine plus put in new valve guides, but I can't really recommend that part since one of mine fell out :tdown:.
Well car is COMPLETELY fixed now, fixed every damn thing wrong with the thing, its running perfectly now and very strong.

The only problem it has now is the HKS EVC 4 isnt reading the boost/vacuum correctly, my friend thinks the stutter box has a problem, the outlet 4 seems blocked, will take a look at it tomorrow, worked on the car all day, so within 2 days actual work, we replaced the head gasket, exhaust gaskets, the thermostat and the gasket, replaced the water pump, cleaned the piston heads, valves, oh and found a random wire from the positive terminal on the battery, was just hanging in the back of the engine bay, we didnt even know what it went to so we cut it, because we had a stock probe gt sitting next to the car for comparison.

The pictures will show everything, well most of it, left out a few things but you can only remember picture perfect moments so often.

And it was deffinetly a blown head gasket, there is a picture of it below too.

You can now close this thread, thanks.
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