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Is this header primary weld leaking?

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Old Nov 3, 2015 | 12:10 PM
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Default Is this header primary weld leaking?

Chasing an exhaust leak on my headers. I definitely found leaks at the slip fit collectors, but I am thinking my one primary is leaking too. ARH offered to take my header in for inspection and free repair if I pay shipping both ways (thought that was very nice of them since I inherited these headers), but its a pain in the *** to have down time and have to ship a header, so I want to be 100% sure before I do the labor.

Attached is the pic. 7 primaries look completely blackened and normal, but one primary still looks almost new, but has a very distinct black area near the weld. Does this look like a leak to you?
Attached Thumbnails Is this header primary weld leaking?-20151103_125453.jpeg  
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Old Nov 4, 2015 | 04:51 PM
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Inspect it but most likely not. Having it welded local will be cheaper than shipping 1 way.

Tim
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Old Nov 4, 2015 | 06:08 PM
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Originally Posted by Gray86hatch
Inspect it but most likely not. Having it welded local will be cheaper than shipping 1 way.

Tim
Thanks, that is what I figured. I am going to pressurize the system this weekend just to be sure though. Tough to find time when you got a newborn though, which is why I made the thread to hopefully get some responses .
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Old Nov 4, 2015 | 07:30 PM
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I'd be more curious as to why 7 of the 8 tubes look to be getting hot and that one isn't.

I would be very interested to see what the plug in that hole looks like compared to the others, I bet you see something that doesn't make sense and you have a dead cyl... whether it's the coil, etc. I have no idea but there's no way that you should have heat in all the primaries except one like that.

It's not a header problem... you have something else going on there.
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Old Nov 4, 2015 | 07:52 PM
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Originally Posted by JL ws-6
I'd be more curious as to why 7 of the 8 tubes look to be getting hot and that one isn't.

I would be very interested to see what the plug in that hole looks like compared to the others, I bet you see something that doesn't make sense and you have a dead cyl... whether it's the coil, etc. I have no idea but there's no way that you should have heat in all the primaries except one like that.

It's not a header problem... you have something else going on there.
It is odd isn't it?

But the car runs smooth and has good power. I put all new ZR1 plugs in and firecore wires too.

Maybe the previous owner had an issue with a plug/wire and the header primary hasn't had a chance to catch up yet? I'll pull the plugs and take a pic on those two cylinders. I can also log misfires, I will plug my scanner in tomorrow.

Last edited by mchicia1; Nov 4, 2015 at 08:36 PM.
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Old Nov 4, 2015 | 09:36 PM
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I wonder if this ticking under load is just a coil arcing...

Oh man I would love for that to be true.
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Old Nov 4, 2015 | 10:06 PM
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I bet you have a dead hole. Why, there's a lot of reasons. Try swapping the coil packs from one side to the other and see if the problem moves to the other side if the plugs look funky, that will tell you if it's a coil or the coil pack harness. Problem stays put, then try swapping wires around.... if it still stays there time to start leaking and compression testing because that's not right.
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Old Nov 5, 2015 | 07:55 AM
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Originally Posted by JL ws-6
I bet you have a dead hole. Why, there's a lot of reasons. Try swapping the coil packs from one side to the other and see if the problem moves to the other side if the plugs look funky, that will tell you if it's a coil or the coil pack harness. Problem stays put, then try swapping wires around.... if it still stays there time to start leaking and compression testing because that's not right.
I was hoping it would be a coil pack last night, but I don't think so, I logged misfires today and there were 0 on all cylinders. The car runs way too smooth too to be misfiring. We left one plug wire loose by accident on my Dad's C6 and it ran like dog **** and the misfires showed up in the scanner.

What I did see in my scanner was on cold start the Bank 1 trims were maxed out to +25% while bank 2 was the normal -5% to 0%. This is definitely indicative of a leak prior to the 02 sensors. The trims came back to normal after about 2 minutes of driving because the heat from the exhaust must be sealing the leak enough to not drive the 02s crazy.

Since the 02 sensors are before the slip fit, I would imagine this means the header flange itself is leaking either at the flange or a weld. Time to hook the compressed air up into the exhaust and poke around I guess. Pain in the *** but has to be done at this point.

Here is an idle vid I took a couple weeks ago, pretty smooth and quiet.

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Old Nov 5, 2015 | 09:57 AM
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Stainkess headers brown with heat and time... If you have one tube that's not doing that I'm sorry but that makes zero sense. In 20 years I have never seen a set of headers do that... Something funny going on
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Old Nov 5, 2015 | 12:37 PM
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Originally Posted by JL ws-6
Stainkess headers brown with heat and time... If you have one tube that's not doing that I'm sorry but that makes zero sense. In 20 years I have never seen a set of headers do that... Something funny going on
I agree it is odd, not a dead hole though. I put my hand above the header and it was smoking hot just like the others.

Here are the plugs side by side. The weird pipe's plug is on the left since pic is upside down.
Attached Thumbnails Is this header primary weld leaking?-sparkplugs.jpg  
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Old Nov 5, 2015 | 12:46 PM
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Video of the sound. It's only noticeable at 1300 rpms or less with high load on the car. Most noticeable at 1:06 because I am going up hill in a high gear. You can hear it clear up when the RPMS go up.

It made the same exact sound when while still on the factory DOD setup, so it's not just valve train noise through the header.

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Old Nov 5, 2015 | 01:26 PM
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Detonation? Any knock?
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Old Nov 5, 2015 | 01:49 PM
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In the first picture, it looks like the header flange is warped.
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Old Nov 5, 2015 | 02:12 PM
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Originally Posted by JL ws-6
Detonation? Any knock?
Nope, car runs great. 0 KR on scanner.

Originally Posted by Jontall
In the first picture, it looks like the header flange is warped.
It is warped, it would not seal at all with stock MLS gasket.

I put thick remflex gaskets on there and that seemed to seal it, at least at idle. With the MLS gaskets on there, you could clearly hear the exhaust leak and see the black carbon on the head.

Sigh, maybe I just need to ship these to ARH and be done with it.
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Old Nov 5, 2015 | 03:10 PM
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Pull it you will see where there's a carbon mark if it's leaking.
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Old Nov 5, 2015 | 03:17 PM
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Originally Posted by JL ws-6
Pull it you will see where there's a carbon mark if it's leaking.
Yeah at this point I think this is the only way.
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Old Nov 6, 2015 | 01:38 PM
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Originally Posted by mchicia1
Nope, car runs great. 0 KR on scanner.



It is warped, it would not seal at all with stock MLS gasket.

I put thick remflex gaskets on there and that seemed to seal it, at least at idle. With the MLS gaskets on there, you could clearly hear the exhaust leak and see the black carbon on the head.

Sigh, maybe I just need to ship these to ARH and be done with it.
You really need to take them off and let ARH repair them. A warped flange is a manufacturing defect and I really don't think those headers can be repaired. ARH should step up and replace them with a new set.
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Old Nov 6, 2015 | 01:58 PM
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Originally Posted by Jontall
You really need to take them off and let ARH repair them. A warped flange is a manufacturing defect and I really don't think those headers can be repaired. ARH should step up and replace them with a new set.
Yeah, I agree, but I was not the original purchaser . These were on the car when I bought them.

They did offer to fix, but I doubt that would be getting a new header but you never know.
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Old Nov 6, 2015 | 03:22 PM
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Warped flange is easy to fix, reweld it, and put the thing on a big belt sanding table... whamo no more warped flange.

Fwiw if you were to dychem the flange on pretty much any header and hit it on a flat table with sandpaper on it you would see none of them are flat, that's one of the things an experienced guy will do with new headers before installing them. Hell I'm going to do it to the set I'm building now.
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Old Nov 7, 2015 | 02:55 AM
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Originally Posted by mchicia1
Yeah, I agree, but I was not the original purchaser . These were on the car when I bought them.

They did offer to fix, but I doubt that would be getting a new header but you never know.
Than you need to send them back. I've heard of other people having problems with ARH defects. I would not try to make the flanges flat yourself because the thinner they get, the more they will warp.
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