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Ralph L
08-28-2021, 11:17 PM
Hi all,
I have an ‘04 that has been with me for 11 years now so very familiar with it but I need some diagnostic help. A month or so ago started hearing an exhaust leak left side when cold, under load, then would stop when the car would get to temp . Now I hear the leak under load all the time. My guess is cracked manifold but wanted to hear any other ideas before I remove to inspect for cracks ( left side is not fun )?
Thanks
Ralph

pokeyl
08-29-2021, 08:03 AM
Is the exhaust all stock? I use plastic flex tubing (fish tank air line) to find leaks. Hazard!! A large leak can damage you hearing!!! I move the tube very slowly around the suspect area. When you get get close you will know. I have been using this approach for over 40 years and have never busted an ear.

Steve-Indy
08-29-2021, 09:44 AM
Sadly, cracks in stock Gen III exhaust manifolds have been reported frequently. May be time to go aftermarket.

Ralph L
08-29-2021, 12:35 PM
Will definitely try the hose idea, forgot that one. Hopefully I can hear it while idling. Has anyone had luck with welding the crack or are they mostly on the flange ? I was also going to replace the motor mount so thinking about removing the manifold. Decisions, decisions… lol

Ralph L
09-03-2021, 06:37 PM
Update !
I had a couple hours and removed the exhaust manifold. As I removed the manifold the gasket fell apart ( see pics ) and I’m assuming that was my problem, I guess ? Adding a few other things like motor mount, spark plugs and thinking of having the valve covers painted.
Thanks in advance,
Ralph 48971

steve911
09-05-2021, 09:57 AM
Even though you may have found a possible source for the leak, keep LOOKING! That is not the traditional location where the manifolds leak. I would hate for you to put things back together and still have a problem.

Steve M
09-05-2021, 10:42 AM
Even though you may have found a possible source for the leak, keep LOOKING! That is not the traditional location where the manifolds leak. I would hate for you to put things back together and still have a problem.

Agreed...it is not uncommon for MLS gaskets to do that.

pokeyl
09-05-2021, 10:44 AM
You can see the leak second from the left. Good find. inspect the head and manifold for damage at that spot. Just use a straight edge to test.

Ralph L
09-05-2021, 11:28 PM
Sorry for the delayed response, we have an 11 month old running the house lol. Took a look again and can’t find a smoking gun on the heads other than an old oil leak from a faulty oil cap. I tried my best to take pics of the head. Also where are the manifold leaks most likely to come from? Was concerned of removing the heat shield and not being able to install it back.
49001

Old School
09-06-2021, 08:07 AM
48971
Header (or any) gaskets usually don't leak around the bolt, they usually leak half way between the bolts, unless that bolt was loose.

Also, headers normally crack adjacent to a weld.

SRT_BluByU
09-06-2021, 09:11 AM
Sure looks like second to left and last on the right were leaking.. loose manifold bolts maybe.