DIY CAT replacment 2004 E320
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2004 Mercedes E320
DIY CAT replacment 2004 E320
Good Morning, I was recently informed that I needed to replace both CATS for my 2004 E320. So far, the cost for replacement is in the range of $2,100 - $2,300. So, my question is, can I do the CAT replacement myself and does anyone have a procedure for doing the replacement and where can I get a good price for replacement CATs. Are their any aftermarket CATS I can use vice using Mercedes CATS. Any help would be greatly appreciated. My car has approximately 158k miles, so I guess CAT replacement makes sense. Finally, if the CATs are only plugged, can they be unplugged.
Duke
Duke
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From: MA
2008 E350 4Matic, 2011 E350 4matic
What error codes are you getting? Usually when the rear O2 sensors have the same readings as the front O2 sensors, that means the cats are shot.
You can buy the cats anywhere, rockauto has them for around $400 each, but it looks like there's two of them. That $2100 sounds like a dealer price. You can try having it done at a muffler shop or just a regular mechanic that would have a lower hourly rate than a dealer.
They usually don't go bad unless there's some other problem like a misfire, air leak or some other problem. You'll want to make sure you don't have any other problems before fixing them otherwise you'll just toast them again.
Usually they can't be unplugged although there are videos out there that claim that they can clean them out. If you're going to DIY it and can waste time doing it twice, you might want to try it. Also keep the old ones, they may be worth around $100 or more as scrap value.
You can buy the cats anywhere, rockauto has them for around $400 each, but it looks like there's two of them. That $2100 sounds like a dealer price. You can try having it done at a muffler shop or just a regular mechanic that would have a lower hourly rate than a dealer.
They usually don't go bad unless there's some other problem like a misfire, air leak or some other problem. You'll want to make sure you don't have any other problems before fixing them otherwise you'll just toast them again.
Usually they can't be unplugged although there are videos out there that claim that they can clean them out. If you're going to DIY it and can waste time doing it twice, you might want to try it. Also keep the old ones, they may be worth around $100 or more as scrap value.
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From: Richmond, CA
2001 E320 Wagon, 2006 LBZ Silverado, 2007 E63 (sold), 2001 E55 (sold)
Where do you live? If you're in CA you have to use OEM cats, which are pricey. Aftermarket cats won't pass the visual inspection.
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From: MA
2008 E350 4Matic, 2011 E350 4matic
Thread Starter
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2004 Mercedes E320
Update regarding CAT situation
First, I want to thank all the DIYers who provided guidance and insight regarding my CAT situation for my 2004 E320. The good news is I took the car to another shop, who informed me my CATS were still good. Whew!!!, but he did indicate that I needed to replace the valve cover gaskets, which I could do myself and replace the front engine mounts. duke
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MBWorld Fanatic!
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2008 E350 4Matic, 2011 E350 4matic
Name the junkyard where they were sold. US Federal law has a large fine for those that do so. I believe it's also illegal for individuals to sell used ones also unless it for recycling purposes. They're much less likely to be caught though.
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2007 cls550
Geez guy, I wasn’t trying to get into a pissing contest about the law. Of course you are correct. All I am saying is that you can get on Craigslist any day of the week or walk down to local yards and find exhaust systems with or without mufflers. I am not talking about crooks who steal and sell cats. Just legit people who have a car totaled and piece it out.
There are other options than spending 2k.
There are other options than spending 2k.
MBWorld Fanatic!
Joined: Feb 2014
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From: MA
2008 E350 4Matic, 2011 E350 4matic
Geez guy, I wasn’t trying to get into a pissing contest about the law. Of course you are correct. All I am saying is that you can get on Craigslist any day of the week or walk down to local yards and find exhaust systems with or without mufflers. I am not talking about crooks who steal and sell cats. Just legit people who have a car totaled and piece it out.
There are other options than spending 2k.
There are other options than spending 2k.
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2007 cls550
You need another yard. Cats only and a full end to end exhaust for a Viper. I didn’t go to Dodge to get them. I just searched Craigslist for exhaust Mercedes and got multiple hits for totaled out cars.
