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Discussion Starter #1
Ok...so... I'm assuming this would go in here... :crazy:

Anyways, I have a leak SOMEWHERE...and it's coming from the engine bay...

-Sounds like an exhaust leak...
-I'm not missing any bolts on the headers.... and the gaskets seem to be in good condition (IE...theres no black around the seals)
-The Y-Pipe / Cats / all the way back is ok

What else should i be checking?!?! (and give specific locations please)

I mainly only hear it on acceleration...but it's starting to occur on startup as well. It sounds like an exhaust leak (which is why i'm checking exhaust components)...and i say that...b/c it's making the same sound it did last year...when i had lost a bolt from the headers..

To best describe the sound...it's sort of a toned down version of when you were a kid...and used to stick a card in the spokes of the rear tire.

Its getting VERY ANNOYING :bawl:

Any thoughts / ideas?
 

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piston slap?? :shrug: thats what my truck has at least
 

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Discussion Starter #5
piston slap?? :shrug: thats what my truck has at least
Wouldn't that happen @ idle as well?

This noise doesn't occur during idle....

EDIT: just listened to a vid of piston slap... definitely not it..
 

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Wouldn't that happen @ idle as well?

This noise doesn't occur during idle....
the only other thing i have to throw out there that my truck is "rattling" but kind of sounds like an exhaust leak...took me forever to figure out what it was. My cats are fucked on the inside, everything is loose inside of them. If thats not it, I can't help you any further :-\
 

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Not sure if this will help but my oxygen sensor had a crack in it which was causing an exhaust leak sound. It was hitting the frame and it finally cracked. Found this out after I replaced the header gaskets because they had a leak too!
 

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Discussion Starter #8
Not sure if this will help but my oxygen sensor had a crack in it which was causing an exhaust leak sound. It was hitting the frame and it finally cracked. Found this out after I replaced the header gaskets because they had a leak too!
Actually... i think that might be it... On startup it started to slightly make the sound...so i popped the hood and my eyes / ears instantly shot towards the back of the engine bay...

I'm going to check it out once the truck cools down. :shake:
 

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My shit ticks too. I need to get a video up. I changed the 02 sensors last week. But I'm pretty sure those bitches were tight.
 
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I know the older rigs could make lifter noise that kinda sounded like a small exhaust leak.
 

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Discussion Starter #13
Actually... i think that might be it... On startup it started to slightly make the sound...so i popped the hood and my eyes / ears instantly shot towards the back of the engine bay...

I'm going to check it out once the truck cools down. :shake:
Sooooo......

I crawled under the truck... checked everything from the O2 sensors back... everything seems ok. Checked all the bolts on the headers again... tightened one up... test drove the truck...still have the sound. :think:

Only thing that really stands out... is near the head on the drivers side... it's blackish / wet. And it's like that after i drive the truck. (Towards the front of the engine. I'll try to snap a pic tomorrow)
 

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Discussion Starter #16
It ended up being a loose bolt. I didn't see it till i started taking pics of everything...

 

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Glad you found the problems, leaks suck! When we redid the header bolts on my truck we ended up using Stage 8 locking header bolts. Found them on jegs.com I'm hoping that will keep them tight.
 
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