M271 Exhaust manifold/front seal ring
#1
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M271 Exhaust manifold/front seal ring
I'm starting to get a low growl from the exhaust ... sounds like time to replace the manifold gasket (A 271 142 03 80)
I would also like to replace whatever donut/seal connects the header pipe to the front exhaust pipe, but I can't find it on parts.com, epc-net, anywhere.
The front to rear seal ring is (A 202 492 01 81), but nobody shows or mentions a header-to-front seal ring or gasket.
Is there even a gasket in there?
Thanks. John
I would also like to replace whatever donut/seal connects the header pipe to the front exhaust pipe, but I can't find it on parts.com, epc-net, anywhere.
The front to rear seal ring is (A 202 492 01 81), but nobody shows or mentions a header-to-front seal ring or gasket.
Is there even a gasket in there?
Thanks. John
Last edited by jkowtko; 07-01-2015 at 02:46 PM.
#3
Super Member
Thread Starter
Okay, took another listen this morning and it seems like it's the manifold gasket that is leaking. So I'll replace that for now.
Went to the dealership this morning, asked them for a price on the gasket and told them it should be around $10 or less. He quoted me $15, and they have it in stock. I said thanks but that's too high, I'll pick it up online since I have time (the leak isn't that bad yet). He then dropped the price to $9.25, so I bought it.
$9.25 is the quoted retail price online, so fyi depending on the local market, the dealer markup can be significant. This local dealership is generally able to give me a "bargain" price of MSRP I'm sure the markup is for the benefit of the service center, which charges the inflated parts price along with their inflated labor charges when you get the car repaired there.
Went to the dealership this morning, asked them for a price on the gasket and told them it should be around $10 or less. He quoted me $15, and they have it in stock. I said thanks but that's too high, I'll pick it up online since I have time (the leak isn't that bad yet). He then dropped the price to $9.25, so I bought it.
$9.25 is the quoted retail price online, so fyi depending on the local market, the dealer markup can be significant. This local dealership is generally able to give me a "bargain" price of MSRP I'm sure the markup is for the benefit of the service center, which charges the inflated parts price along with their inflated labor charges when you get the car repaired there.
#4
Super Member
Thread Starter
Replaced the manfold gasket this morning ... and it wasn't the problem! Argh ... noise still there. But at least I know how to change an M271 exhaust manifold gasket now
#5
Super Member
Thread Starter
A couple of quick updates --
* There apparently is no gasket between the manifold/cat assembly and the frotn exhaust pipe. It's supposed to be a metal on metal flange connection.
* I bumped into to a tech I know yesterday and asked him about the exhaust leak. He said on the M271 with the integrated cats, the weld seam at the top of the cat often separates. I took another look and there are a few seams in there, so I'll have to check this one out more closely. The good news is that if there is a crack in the seam it should be easily mended by a weld.
* There apparently is no gasket between the manifold/cat assembly and the frotn exhaust pipe. It's supposed to be a metal on metal flange connection.
* I bumped into to a tech I know yesterday and asked him about the exhaust leak. He said on the M271 with the integrated cats, the weld seam at the top of the cat often separates. I took another look and there are a few seams in there, so I'll have to check this one out more closely. The good news is that if there is a crack in the seam it should be easily mended by a weld.
#6
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Thread Starter
Fyi, here is the leak ...
I found a local welder who says he can fix it no problem (it's stainless steel) ... now I just have to find the time and motivation to pull it off the car and bring it in ...
I found a local welder who says he can fix it no problem (it's stainless steel) ... now I just have to find the time and motivation to pull it off the car and bring it in ...
#7
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2003 C230K Coupe Orion Blue
Thanks for posting this. Found a crack in the same location. Never would've looked here in a million years. I just sealed mine up with high temperature epoxy.
Last edited by slammer111; 04-21-2022 at 08:15 AM.
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#8
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So I am hear some sounds coming out of my engine I am assuming it going to the be same crack or the exhaust manifold gasket since iv'e never replaced it.
What's strange is that the only time I really hear the sounds is in reverse I guess when the rpm's are at a certain range once i give it gas noise kinda goes away nonetheless it's bound to be the exhaust manifold when I did the timing chain I noticed black soot right above the exhaust manifold so leads me to believe there's a leak there and needs to be replaced.
When you did this change did you remove the manifold completly off disconnecting the o2 sensors or was it just the bolts holding the manifold and the one bolt on the bottom bracket?
Thanks
What's strange is that the only time I really hear the sounds is in reverse I guess when the rpm's are at a certain range once i give it gas noise kinda goes away nonetheless it's bound to be the exhaust manifold when I did the timing chain I noticed black soot right above the exhaust manifold so leads me to believe there's a leak there and needs to be replaced.
When you did this change did you remove the manifold completly off disconnecting the o2 sensors or was it just the bolts holding the manifold and the one bolt on the bottom bracket?
Thanks
#9
Super Member
Thread Starter
So I am hear some sounds coming out of my engine I am assuming it going to the be same crack or the exhaust manifold gasket since iv'e never replaced it.
What's strange is that the only time I really hear the sounds is in reverse I guess when the rpm's are at a certain range once i give it gas noise kinda goes away nonetheless it's bound to be the exhaust manifold when I did the timing chain I noticed black soot right above the exhaust manifold so leads me to believe there's a leak there and needs to be replaced.
When you did this change did you remove the manifold completly off disconnecting the o2 sensors or was it just the bolts holding the manifold and the one bolt on the bottom bracket?
Thanks
What's strange is that the only time I really hear the sounds is in reverse I guess when the rpm's are at a certain range once i give it gas noise kinda goes away nonetheless it's bound to be the exhaust manifold when I did the timing chain I noticed black soot right above the exhaust manifold so leads me to believe there's a leak there and needs to be replaced.
When you did this change did you remove the manifold completly off disconnecting the o2 sensors or was it just the bolts holding the manifold and the one bolt on the bottom bracket?
Thanks
That being said, I just did replace the post-cat O2 sensor on our Toyota Sienna ... it had no rust on it, but I sprayed it with a bit of penetrating oil before trying to muscle it loose. It broke free without too much effort and I was able to remove and replace it pretty easily. On the M271 pipe I believe the O2 sensor mount is integral with the manifold, isn't it? So you would need to either remove the sensor from the exhaust pipe or leave it on and unclip the wiring from the chassis.
-- John
#10
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2003 C230K Coupe Orion Blue
The crack doesn't really result in any noise. I only found it by accident while trying to diagnose a problem with a weird fume smell in the engine bay that was wafting into the cabin.
#11
Member
I ended up removing the manifold and had it welded at a muffler shop. The noise could've been from the gasket itself since there was black soot all around it.
In either case swapped out the gasket and had the crack welded up well see if I hear any other odd noises practically everything on engine has been replaced or repair by now.
Thanks
In either case swapped out the gasket and had the crack welded up well see if I hear any other odd noises practically everything on engine has been replaced or repair by now.
Thanks
#13
Member
As of now I think so haven't noticed it nor have I driven it enough to be certain. It usually happens when I am reversing the car makes a rattle sound when turning off assuming that was probably the old gasket. The check engine light came on a few hours after 02 sensor p0130 so I have to tackle that next. The o2 sensor maybe was damaged when we put it back together?