Diagnose this sound...

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son comes in from school today and says my truck is making a real loud and weird noise...

I parked it around midnight and it hasn't been cranked since, so I was a little curious to say the least. Go outside and this is what I hear:



Appears to be a cicada or something between the gas tank and tank shield? :eek:
 
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Perhaps a loose heat shield on the catalytic converter, had one corner weld come loose and it chirped all the time.
 
Loosen the gas cap and see if it stops.

-R
Why?

Curious because I did, and it stopped. :eek:

But I'm fairly certain it's simply because it made a noise. I walked away and in about 10 seconds it started back.
 
Leave it loose and see if it starts again. There might be an issue uncovered by pressure.

-R
Seriously...I've crawled under the truck and am 99.44% sure it's nothing but a cicada bug stuck under there. But it's loud!! Drove the truck to pick up supper and it was making the same racket when I came back out.



 
That doesn't sound like a cicada to me, but I can't tell you what it is. In the first video of the two above, it sounds a lot like a wirefeed welder.
 
That doesn't sound like a cicada to me, but I can't tell you what it is. In the first video of the two above, it sounds a lot like a wirefeed welder.
I may go get the hose out and see if whatever it is flushes away...and take a pic if I see it.
 
I may go get the hose out and see if whatever it is flushes away...and take a pic if I see it.

Before you get the driveway wet, crawl under there with the truck running and push on things with a screwdriver, or better, a wood dowel. See if you can touch something that changes or stops the buzzing.

I have to say this (sorry)...set the parking brake before you crawl under.
 
Before you get the driveway wet, crawl under there with the truck running and push on things with a screwdriver, or better, a wood dowel. See if you can touch something that changes or stops the buzzing.

I have to say this (sorry)...set the parking brake before you crawl under.
Already went through all that. I can roll under the truck with it sitting in the ground. Got my ear right next to the gas tank and the shield that goes around it. It's definitely isolated to that area.

Again...it's making that noise sitting still and not running.

Whatever it was just know we're talking about it, as it was completely silent when I went looking for it.

Maybe not a cicada, but some kind of insect. The noise isn't consistent like a rattle/vibration, especially since it's happening without the motor running. The sound fluctuates in volume and speed...similar to the other nature sounds in the yard. It's not just a consistent noise.
 
...

Again...it's making that noise sitting still and not running.

Whatever it was just know we're talking about it, as it was completely silent when I went looking for it.

Maybe not a cicada, but some kind of insect. The noise isn't consistent like a rattle/vibration, especially since it's happening without the motor running. The sound fluctuates in volume and speed...similar to the other nature sounds in the yard. It's not just a consistent noise.

I didn't catch the part about you hearing it with the engine off...thought the truck was running. Is the fuel pump in the tank? I can sometimes hear the pump running on my jeep (FCA product, also).

Maybe it's the audio on my computer, but it sounds metallic to me, not organic.
 
I didn't catch the part about you hearing it with the engine off...thought the truck was running. Is the fuel pump in the tank? I can sometimes hear the pump running on my jeep (FCA product, also).

Maybe it's the audio on my computer, but it sounds metallic to me, not organic.
Probably combination of iPhone mic, YouTube, and your audio. Sounds organic to me.

Pump in tank like my TJ, IIRC. But it shouldn't be making any noise without a key in the ignition.
 
I didn't catch the part about you hearing it with the engine off...thought the truck was running. Is the fuel pump in the tank? I can sometimes hear the pump running on my jeep (FCA product, also).

Maybe it's the audio on my computer, but it sounds metallic to me, not organic.
What I was thinking. Sounds metallic.
 
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I am not buy my work computer to look up part locations but I am thinking maybe an air suspension compressor or maybe an evap system leak detection pump running. It could also be the evap vent soleniod going crazy. Mopars do wierd electrical crap from time to time.
 
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I'm thinking this thread has more trolls than mechanics. o_O
 
Wait a minute, we never claimed to be mechanics, just smart assed comment makers..... You'll have to wait until Monday for the mechanics to show up...
If you're convinced it's an insect take it to a car wash and ask for the underbody flush along with the wash. You may still have the sound but your truck will be clean....sorry couldn't resist....
 
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When the truck has been sitting enough to get cool, get under it and reach around to the top of the gas tank to find the outlet. Then start the truck. Then come tell me which hose is cracked. Then go to your fave parts store and get a new hose section clamp and carbon filter.
 
If you don't think it's the gas tank venting... The only way I know of to eliminate the truck is to disconnect the battery.

Still there? It's possessed and it needs an exorcism.:eek:
An exterminator.o_O
Maybe both...:rolleyes:

-R
 
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Did taking off the gas cap make it stop? Then the noise restarted with it still off ?
 
I got it figured out and it's been fixed. Turns out I needed a new muffler bearing (bought this one), and prepped it with some elbow grease (available here) before installing it.
 
Be serious. Did you figure out what it was or not?
It was just a Dodge thing.

While I looked and looked for the rattler, I'm going with my answer in the original post:

Appears to be a cicada or something between the gas tank and tank shield? :eek:

It's either dead now, or found it's way out. Haven't heard the noise since last night. Neighbor heard it yesterday as well and thought it was a bug in a tree. The audio for y'all must've just made it sound more metallic/man-made than it really was.

Wasn't ever really a question to me...just thought it would be fun to post. And amazed how many people missed the fact the truck wasn't running in any of the videos posted. Not to say it couldn't have still actually been the truck, but I never thought it was.
 
Alot of cars run evap tests when they are off. Newer cars modules stay active for hours sometimes after the ignition is turned off.
 
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