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2007 Pilot makes loud exhaust sound in rain

Hi all,

I just discovered that my 2007 Pilot is making a loud exhaust sound (sounds like coming from under the hood) when it’s raining. It doesn’t last for a long time, but seems to be every time I hit a small puddle.
I just had the oil changed and the transmission fluid flushed or whatever the A3 meant on the car. The car died the next day and replaced the battery.
Does anyone know what could be the problem?
Thanks!

The services you list may have required removal the lower engine shroud.

These protect the engine from water spray so things like exhaust components aren’t hit with cold water, or water gets between the serpentine belt causing slipping of the belt.

See if this shroud is in position.

Tester

Could be the noise of a belt slipping.

Could you tell me where I would find that part you’re mentioning? I don’t know anything about cars, but would like to possible be armed with solutions before paying a ton going to the dealer. Does that piece have a name?
Thanks!

It’s located under the front of the vehicle.

Tester

Thanks!
Will have to check that in the morning since it’s pitch black here and raining.
Can I ask you if it’s dangerous to drive like that if that happens to be the problem? For a split second in the rain today it almost seemed like the steering was tight. But maybe that was just me nervous about the noise it was making.

And there’s also no need to go the dealer for repairs like this. An independent mechanic would probably be cheaper and more willing to troubleshoot a 12 year old Honda.

Dealers like to work on newer cars…and also replace everything worn on the car with expensive parts and labor.

Thanks! I’m taking it to an independent Honda/Acura specialist tomorrow to troubleshoot. Problem is, doesn’t make the noise if it’s not raining. Went to Honda today and he said there’s a slow exhaust leak (something about the flanges) and sent me to a custom exhaust place that wants around $750+ tax for that plus the leaky muffler on top. Although the second place said that puddles wouldn’t have anything to do with the exhaust noise. They ran it through the car wash at Honda and still no noise. Guess it’s not the same as a puddle spraying underneath the car. I’m a lil aggravated that the noise didn’t start until I gad that A3 service done.

Something about the flanges needs to be repaired, but they say that that has nothing to do with the sound it would make when I drive over a puddle.
I also called a few Honda specialists and none of them can tell me what the problem is without me bringing it in.

That flex section looks to me like it has several holes where it is leaking and needs to be replaced.
Here’s what it should look like albeit not as shiny as when new-

Capture

Take the car to a muffler shop, if you suspect an exhaust problem. Again, they will be much cheaper than the dealer.

Honda did refer me to an exhaust shop for the leak, but he said that the exhaust wouldn’t have anything to do with the loud noise it makes when you hit a puddle.

Water splashing on a hot exhaust part could itself make a sound. “Sizzle” or “Whrmmmmp”, something like that. It’s also possible water could cool a hot exhaust juncture, opening it and causing a temporary exhaust leak, which could make that annoying “rat-a-tat-tat” noise.

That’s what the muffler shop told me. He said the noise I’m hearing is completely unrelated to the exhaust. He said there’s something else going on. I’ve called around to Honda specialists looking for answers and taken it back to the Honda dealer and to the exhaust shop they recommended and I’m back to square one. No one has a clue what I’m talking about and since it’s not raining, I can’t make the sound appear.

Are you certain the noise you hear sounds like exhaust noise, like a loud motorcycle? Not a squealing sound like a slipping belt?

Yes. 100% positive. Motorcycle was how my 12 year old described it driving home in rain on Sunday. To me it sounds like the muffler fell off but coming from the front of the car.

Ask your shop to check for a cracked exhaust manifold.