2004 Blowing Steam From Tailpipe After Rain

I haven't ever seen this before. My recently purchased 2004 Taco is blowing steam from the tailpipe after it sits in the rain for a prolonged period of time. This never happens when it's dry out. I'm pretty certain it's not smoke because it only happens when it rains and it doesn't smell like smoke. It looks, moves, smells, and feels like a large cloud of water vapor that lasts for only a few minutes. Then it's gone until the next rains come along only to happen again.

I put a hose on the hood and saw a concerning amount of water coming out of the underside of the engine bay. Here's a video: https://photos.app.goo.gl/sb6fk19TCuXFXW6UA.

Now, I would expect there would of course be steam as the water evaporates off hot surfaces in the engine bay. However, there is a large amount of steam coming directly from the tailpipe. I'm perplexed why water on the engine would blow steam out of tailpipe.

Has anyone ever encountered such a thing? I'm afraid the problem is related to more than just some ineffective weatherstripping that needs replaced.

 

Sounds like condensation in the exhaust.

 

That's what I thought but it's A LOT of condensation. I get huge thick plumes for about 4 to 5 minutes when it happens. I haven't been able to get a video of it in full effect yet.

 

Ouch.
Either some water is leaking into the emissions system or your exhaust or your engine is fucked.

 

I'm betting the engine is fine. Two different mechanics said it's great shape. Also, the water isn't anywhere close to the block.

From what I can tell, water runs down the firewall, but no further inward towards the engine. I can't track it any more than a few inches from the top of the firewall. Is it possible it collects in the exhaust manifold?

Just had the exhaust put on last week. That could be a possibility, but they only did the cat back. How could water be getting in there?

 

I had the same problem when I bought my '04. Freaked out one cold (for LA) morning, and put coolant sealer in the coolant.

Turned out it was nothing, just condensation.

 

Don’t sweat it, tell everyone you are spraying for skeeters...

 

If the steam from the exhaust doesn’t smell like coolant I wouldn’t be too worried.

 

Every gallon of gas burned creates a gallon of water. I suspect you only see the water vapor when it's raining because the humidity is high. When it's not raining and humidity is low you don't see it.

 

subbed because i want to see the video when you upload one

 

If water can get into the exhaust from outside your going to have an exhaust leak!!

In high winds and heavy rain if the exhaust exit is level or tilted up you might get some water.

If it comes from the engine it is going to be coolant and keep spraying to the coolant is gone .

Which also would happen all the time .

Are you adding coolant all the time maybe a gallon every few miles

 

Coolant levels are stable. Just had a new radiator put in and the valve cover gasket replaced. I think that even if some water was blowing into the tailpipe, it couldn't be that much. I've also had a few bad head gaskets on other vehicles and am very familiar with the smell of burning coolant. I don't smell anything that would suspect coolant or oil leaks.

Being from Ohio, I'm very familiar with seeing some water vapor in colder weather. What I'm experiencing is about 1000 times more vapor than that and it's 80 degrees here now.

 

Well, it stopped raining and no more is forecast for the rest of the week, so it might be a while. But as soon as it happens again, I'll record it. It really is amazing how much steam is kicked out.

 

Your not hitting deep puddles and the hot cats are causing the steam.

From the rapid cooling of the exhaust

 

Not at all. Only on startup. After about 4 to 5 minutes, it's done and everything is fine.

 

Wonder if it’s brake fluid being pulled by the vacuum lines or something. Brake fluid level fine? Oil level still normal?
Shouldn’t smoke as much as you describe. Seems a bit much. Does it run/sound any different when that much smoke is coming our the tail pipe?

 

Finally got a video:



I saw water dripping from some crappy welds in the exhaust. Pretty certain water is getting in there, just can't figure out how. I'm going to have to take it back to the shop that put on the exhaust. Glad I got a video of it now.

 

Yeah, that definitely seems excessive. If it doesn’t smell of antifreeze and your fluid levels aren’t changing then it would be water. Just not sure how it would get into the exhaust. Seems it would also be blowing out water droplets from the tailpipe.

 

I hope I am wrong but it looks like a head gasket or head. Pooled rainwater in the exhaust wouldn’t steam until the exhaust heated up a relatively long time after startup. This is happening right at startup so I’m thinking coolant leak that seals when head, block and/or manifold heats up. I don’t think it’s related to ambient humidity, I’m in Florida and short of Hell, there is no place more humid and cars here don’t smoke like that. Keep checking your coolant, you have got to be losing some.

 

That's a lot of water vapor, way more than normal. Something is wrong. I've heard of chemical tests for head gasket leaks, that's what I'd try next.