My car is steaming or (please, God, no...) smoking? [Resolved]

nakirush

Hey H/A,

I am not a car guy, by no means whatsoever. I'm at a complete loss here and would love your help. I drive a '93 Mazda Miata.

I was driving home from the drugstore and as I stopped at a traffic light I noticed a ton of "fog". After a second I realized it was smoke coming from under my hood. Freaked out I pulled into a gas station and popped the hood to take a closer look. I'm not sure if it was smoke or steam. It didn't smell smoky, kind of oily I guess? Upon closer investigation it seemed the smoke/steam was coming from the back passenger side of the engine (right next to the oil checker thing). I checked the oil levels and they're fine. I have no idea what the problem was as it just came up out of the blue.

Ideas?

Aurin

Did the oil look odd at all? Goopy? Bubbles? It could be a lot of things... But looking at the oil can give you a good indication of what it might be. Check the antifreeze as well, you might have just blown a cooling hose. Is the car running hot? Another way to get more information on it is to see if it's leaking anything...

Do you know someone who's a car person? Or perhaps someone who knows a good mechanic?

The Black Hunter

When was the last time you changed the oil etc?

BlindZenDriver

Step. 1 . Check fluids - there is more than just oil. Like Aurin suggests it could be coolant but there is several other types. From the location you give it could be oil leaking out from the valve cover which while it may sound serious is likely just a gasket that needs replacing ($20 or so in parts).
Step 2. Go to miata.net and seek help, check the many articles in the "Garage" section and if that does not bring anything then their forum is really great. It's the best place for anything Miata.

PS. I drive a '99 :-)

Adus

It could potentially be low on coolant. Does your heat gauge work? I've had two cars produce this similar situation with different causes, one being the coolant whereas the other had an oil leak which would drip onto heated parts of the engine and cause steam.

WildEEP

Color of the smoke can sometimes help.

Black is carbon
Blue is oil
White is water.

If its oil, there are only so many places it can come from. Is the Engine light on?

If its coolant/water, it may be the thermostat. If you start your car, you should be able to open the radiator cap and see what looks like a little river running past inside the hole.

Carbon can be anything that gets spilled onto your engine and burning off when it gets hot.

JebusUD

Fog type smoke is almost 100% the car overheating.

Check the coolant, it is probably gone. Don't drive it anywhere, you will melt the cylinders to the block. Or crack a cylinder or break the head gasket.

Pel

Take note of the color, as previously said. Are any warning lights on? Is your temperature stable? The most likely culprit is steam from an overheating engine, as said, but the coolant system is almost entirely towards the front of RWD cars such as the Miata. Smoke coming from the rear of the engine compartment is more likely from a fluid reservoir overflowing onto the exhaust as it travels under the engine: Power steering fluid seems possible, brake fluid, transmission fluid from a broken line, or even oil. It's not wise to drive a car with any of these things running low, but most of all if your "Oil" or "temperature" light comes on even for a short time, immediately shut off the engine. Driving a car with no oil pressure or a temperature problem even for seconds can result in catastrophic damage. I guess the bottom line here is that you should immediately check all fluids and proceed with extreme caution when driving, if you don't do the safe thing and have it towed somewhere where someone who knows what they're doing can look at it.

Edit: Miata is RWD, dur.

mts

sounds like an overheat/blown radiator

Spudge

Both the antifreeze and wiper fluid reservoirs are on the passenger side. Check them both for damage (could have leaked onto the exhaust manifold)

nakirush

Update: I checked the coolant and it was completely empty. I filled it up, started the car and let it run for a few minutes with no problems. I drove the car a mile and let it sit to see if there was any smoke. No problems yet. I drove back home (another mile). On the way back I stopped at an intersection and heard a click. When I stopped to pull into my driveway I heard three more clicks then a hissing sound. I pulled into my parking space and there was white smoke coming out of my hood again. Mechanic time?

JebusUD

nakirush wrote: »

Update: I checked the coolant and it was completely empty. I filled it up, started the car and let it run for a few minutes with no problems. I drove the car a mile and let it sit to see if there was any smoke. No problems yet. I drove back home (another mile). On the way back I stopped at an intersection and heard a click. When I stopped to pull into my driveway I heard three more clicks then a hissing sound. I pulled into my parking space and there was white smoke coming out of my hood again. Mechanic time?

You have a coolant leak. If you look at the coolant resovoir again it will be empty. If you don't know anything about cars or know anyone who knows anything about it it isn't going to be fixable by yourself. So mechanic time.

nakirush

Ugh. It may be a long list of possibilities, but any idea how much I may be paying for this?

Adus

Potentially over a thousand dollars if your radiator is busted.

JebusUD

Adus wrote: »

Potentially over a thousand dollars if your radiator is busted.

It's not likely busted though. More likely just one of the tubes broke. If you really wanted to know you could put more coolant in and look for it leaking, might even see the leak without the car running. If that doesn't work you could leave the hood open and run it, after putting in more coolant, but only for a short period. Sometimes you can see coolant spray from leaky tubes, and you will see a puddle under where it is leaking. If you do this though, make sure to turn it off before all the coolant leaks out or you will overheat again.


Still, don't drive it anywhere. Have it towed to the garage if you are taking it to one. If all the coolant leaked out going just a mile down the road you will never make it to the garage intact.

Overall cost is likely to be different depending on where you live and who does the work. As long as it isn't the radiator then parts will not be too expensive. I'd say max 150$. Labor is what is going to get you. probably knock it up to around 400$ or 500$.

If it is the radiator then it is gonna cost an assload of cash, potentially enough to not even make it worth fixing, depending on its general condition.

The moral of the story is to make friends with a mechanic so labor is free (or cheap as a pack of beer).

wmelon

JebusUD wrote: »

Adus wrote: »

Potentially over a thousand dollars if your radiator is busted.

It's not likely busted though. More likely just one of the tubes broke. If you really wanted to know you could put more coolant in and look for it leaking, might even see the leak without the car running. If that doesn't work you could leave the hood open and run it, after putting in more coolant, but only for a short period. Sometimes you can see coolant spray from leaky tubes, and you will see a puddle under where it is leaking. If you do this though, make sure to turn it off before all the coolant leaks out or you will overheat again.


Still, don't drive it anywhere. Have it towed to the garage if you are taking it to one. If all the coolant leaked out going just a mile down the road you will never make it to the garage intact.

Overall cost is likely to be different depending on where you live and who does the work. As long as it isn't the radiator then parts will not be too expensive. I'd say max 150$. Labor is what is going to get you. probably knock it up to around 400$ or 500$.

If it is the radiator then it is gonna cost an assload of cash, potentially enough to not even make it worth fixing, depending on its general condition.

The moral of the story is to make friends with a mechanic so labor is free (or cheap as a pack of beer).

Honestly It shouldn't be anywhere NEAR $1,000 to replace the radiator on a miata. The OEM radiator is only a little over $200. Aftermarket radiators can be had for less than $100 and should be less than 3 hours of labor to replace. My guess based on where you describe the smoke/steam coming from would be that one of the hoses from the block to the heater have sprung a leak. They're a bit difficult to get at, but can be replaced without involving a mechanic.

I'd recommend replacing ALL of your radiator/heater hoses. For the heater hoses, I'd also recommend getting the pre-formed ones. I just looked up the costs of the hoses and you should be able to get all 4 of them for less than $30, then it's just a matter of new clamps which you can get for less than $10. If you can handle a screwdriver you should be able to replace these hoses without a problem.

mts

we paid like 300 to replace the hoses. if the radiator is cracked thats probably another 300 bucks

nakirush

I just got back on my lunch and checked the coolant levels. The coolant tank is still full, so it didn't all leak out in two miles. I'm guessing it's just spraying on the engine and making lots of smoke? Since it didn't all leak will it be safe to drive it a few miles to my mechanic?

Djeet

If you need to drive with a minor coolant leak you can do it. You'll need a big jug of coolant/water in the passenger seat or boot and you'll need to make sure to immediately pull over and shutoff engine when the temp gets over about halfway on the dial. And then let engine cool down and refill with coolant/water*. If you let engine get too hot you're fucked (warped cylinder heads or worse).

Parts wise a new hose is going to be $10-20 and a new radiator $100-200. Labor could be under an hour for a hose or 2-3 for a radiator. Plus factor in enough coolant (8$/gallon?) to refill plus shop fees and disposal (10-20). You're best off diagnosing what work needs to be done (hose vs radiator) rather than have them diagnose.


*Edit: Having limped home myself this way it's important to note that when you shutoff your engine that's approaching the overheat state you want to make sure you turn your key to the ACC position or whatever position leaves the engine fan on. Or just get a tow.

Casual

Adus wrote: »

It could potentially be low on coolant. Does your heat gauge work? I've had two cars produce this similar situation with different causes, one being the coolant whereas the other had an oil leak which would drip onto heated parts of the engine and cause steam.

Most likley this. Or (I hope not for your sake) the radiator is fucked.

Pel

nakirush wrote: »

I just got back on my lunch and checked the coolant levels. The coolant tank is still full, so it didn't all leak out in two miles. I'm guessing it's just spraying on the engine and making lots of smoke? Since it didn't all leak will it be safe to drive it a few miles to my mechanic?

It's possible that your car overheated for a different reason and this is why your coolant was gone. If this is the case, the coolant level might be fine for a while, until whatever caused your car to overheat strikes again. Possible causes: Dying water pump, malfunctioning thermostat, head gasket...

If the car overheats, then the superheated coolant will escape through whatever means possible: usually a relief valve built into the radiator lid. Overheating car leads to steam and low coolant. If your coolant doesn't seem to be leaking, and your car overheated once, then that probably means that the low coolant level was caused by the overheating and not vice versa.

Zeon

Dont drive a car with a coolant leak. Coolant lines need to be bled whenever the level drops below minimum. If youre not comfortable doing this (its usually a screw at the highest point in the cooling system) youre potentially causing more damage to the car. Air in the lines doesnt cool the engine at all and can cause more overheating, plus inefficient coolant flow. You can turn a couple hundred dollar repair into a couple thousand if you end up warping the block or seizing the engine.

Get it towed to the shop. More than likely one of the rad hoses is broken or has come loose. If you insist on driving it, dont be surprised if your engine locks up.

MyDcmbr

Sounds like the coolant line that goes to your heater core. Should be a foot or so of 3/4" black rubber tube and a couple of hose clamps to fix.

mts

well as long as the car is not overheating it can be driven. before i had it replaced because of a crack, i was driving around with no coolant for a long time, no overheats at all

Tef

If it is something as simple as a busted hose, I reckon you should either get one of your mates who's handy to look at replacing it for you with a cheaper part. Unless you have an awesome mechanic, mechanics will make you pay through the nose for what would (if it's just a busted hose or seal) be a very simple job

Spudge

Couple clicks, then steam? After driving it a while, and I dunno maybe getting it to operating temperature?

Check your thermostat housing. More importantly, check the bleed screw on top of the thermostat housing. I'll bet it's loose, or the hose has cracked in that specific area

wmelon

The thermostat is on the front of the engine in the miata. It also doesn't have a bleed screw. The radiator cap is the high point in their cooling system.

If it's not a leaking hose, I'd expect it to be one of the things in this picture.

nakirush

Got it into the mechanic and he found the leak. I'll have my car back tomorrow morning.