Stock headers won't seal
 

Hello everyone, first off I'd like to introduce myself since this is my first post on here. My name is Chris and I recently purchased an 01 Boxster S with 22,000 miles on it :cool: I've been an avid car guy for years and I currently own the Boxster, an 02 Ford Lightning and a 97 Cobra.

Ok now on to my problem. The Boxster has recently developed a very bad exhaust leak from the headers. I purchased new gaskets and installed them but that didn't help at all. It's leaking so bad that it's throwing a check engine light. I have removed them about three times now to get them to seal and still nothing works. I'm beginning to wonder if the headers are warped. Has anyone had this problem? What should I do from here? I've tried coating the gaskets in copper RTV which has always worked for me but this time it did nothing.

Thanks!

Do you have a straight edge, metal ruler to check the flange? The CEL, have you had the code read to insure that the exhaust leak is throwing the code? If yes, what was the code?

I have not checked them with a straight edge yet but I am going to pull them off and take them to work. I work in the aviation industry and we have a nice machine shop at work. The CEL was read but I don't remember the exact code. It was basically saying the engine was running rich and the guy who scanned it agreed with me that the exhaust leak would cause it to run rich due to the 02 sensors detecting fresh air from the header leak and trying to dump more fuel to compensate. First things first I want to fix these leaks and then if the CEL stays on I'll go from there.

So far I am not happy with this car. With only 26,000 miles on it I have a CEL, Exhaust leak and also the right rear wheel bearing is bad.

Ensuring that the header flanges are true prior to installation is a necessary evil with ALL aftermarket headers... I have yet to see a single one that was adequately decked out of the box. Most are made in China, the land of non existant attention to detail and then re-sold by people that don't know what the sealing surface is supposed to look like..

Until you pull the headers and have them decked true you can expect to have this issue and some are worse than others.

This is another reason why we are building our own!

I understand that but in this case I'm using the factory Porsche headers and not aftermarket. I would hope that Porsche built them well enough to not warp after 22,000 miles. This car was previously owned by a 65 year old woman who took meticulous care of it. It has all the receipts from Porsche and all the regular maintenance was performed. I also notice the CV boots and the clutch was replaced at only 10,000 miles. I hope this isn't a sign of how unreliable this car is going to be.

I can understand the CV boots being replaced at 10K. It could have been just time rather than miles. But the clutch? I dunno what to think about that unless it was the dealership drumming up warranty work...

He did say a little ol' lady was the last owner. Unless she knew how to properly use a clutch I can see it being replaced in 10,000 miles. I remember one being replaced on a VW in 3,000 miles! This lady rode the clutch so much and it wore it down to the rivets! The flywheel had turned color because of the heat from the slipping.

They are likely leaking from heat warpage. This can happen even to factory collectors, especially if they're not properly torqued.

As mentioned, the solution is to have them decked. But, removing material from the flange will only increase their propensity to warp in the future.

To minimize this, ensure you're removing as little material as absolutely necessary.

Set up a dial gauge and take as many data points as you can, especially from around the ports and only machine the flange as deep as the largest variation. You can use a straight edge and feeler gauge too, but it won't be quite as accurate and you may remove more material than necessary.

Are you sure that it's leaking where the flanges seal to the heads? You might have a crack in one (or more) of the primary tubes at the flange. My 2000 S stock header/cat units recently developed this condition, and it's hard to see with the headers installed on the engine. I have no fault codes yet, but there is some noise.

I'm pretty sure it's the headers where they meet the heads. The old gaskets were black all the way to the edges which means exhaust gas was leaking out there.

I was TOOL, I thought that you were having issues with aftermarket headers not sealing. Sorry about that.

No worries man I appreciate the help either way.