Replace Cats/o2 sensors
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Joined: Aug 2018
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From: Connecticut
E350 4MATIC 2011 W212/S550 4MATIC 2012 W221
Replace Cats/o2 sensors
Cost to replace o2 sensors and catalytic converters 2011 E350 4matic 204kmiles? Had 200k service done at dealer no indications cats were bad. Drove car 600 miles cel. Codes p0420,p0430.
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'11 E350, '11 E550, '98 M3, '95 E320
Expensive… just did one on a 211. One side, from dealer, $1000 + labor. Reason, it was damaged earlier when the front driveshaft let go and took out the PS rack and part of the engine housing.
W212 ones look to be $1200-1800 for the pair, plus labor.
W212 ones look to be $1200-1800 for the pair, plus labor.
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From: FL
2012 E550 sedan 2019 E63 Wagon
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From: V E G A S
1922 Ford Model T / no OBD
Email this guy.
They can custom-make CAT in Poland, so it will take time, but hard to beat the prices.
https://wl-parts.com/direct-fit-catalytic-converters/
They can custom-make CAT in Poland, so it will take time, but hard to beat the prices.
https://wl-parts.com/direct-fit-catalytic-converters/
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From: MA
2008 E350 4Matic, 2011 E350 4matic
Did you have it diagnosed? Could also be some kind of an air leak somewhere. Most likely it's the cats though, but you should make sure it's the cats before just replacing it due to a code. I would have changed the upstream sensors in the 100k range.
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Joined: Aug 2018
Posts: 24
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From: Connecticut
E350 4MATIC 2011 W212/S550 4MATIC 2012 W221
replace cats
I had the car scanned several times. First when codes appeared and scanner said codes were permanent. My mechanic says the codes have been there for awhile and someone cleared them... This happened during a 600 mile trip. Cleared CEL only to have it return when at end of trip! Prior to trip had 200,000 mile service done. Asked service manager if cats and o2 sensors should be changed due to mileage? Answer was no, "Do not change unless necessary! There are 2 cats and 4 sensors and it could be expensive." Car has over 200k on it and was regularly serviced by the dealer prior to me buying it. So, I figured all was good. I ordered the cats and o2 sensors and I am waiting there arrival to have installed. Car has been great and no loss of power or acceleration. Be up and running soon.
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MBWorld Fanatic!
Joined: Feb 2014
Posts: 6,190
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From: MA
2008 E350 4Matic, 2011 E350 4matic
I had the car scanned several times. First when codes appeared and scanner said codes were permanent. My mechanic says the codes have been there for awhile and someone cleared them... This happened during a 600 mile trip. Cleared CEL only to have it return when at end of trip! Prior to trip had 200,000 mile service done. Asked service manager if cats and o2 sensors should be changed due to mileage? Answer was no, "Do not change unless necessary! There are 2 cats and 4 sensors and it could be expensive." Car has over 200k on it and was regularly serviced by the dealer prior to me buying it. So, I figured all was good. I ordered the cats and o2 sensors and I am waiting there arrival to have installed. Car has been great and no loss of power or acceleration. Be up and running soon.
https://www.fixdapp.com/blog/p0420-code/
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Thread Starter
Junior Member
Joined: Aug 2018
Posts: 24
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From: Connecticut
E350 4MATIC 2011 W212/S550 4MATIC 2012 W221
Scanning it and actually checking the car over for air leaks and other loose parts or damage are two different things. Of course if there was an air leak, then it would be permanent until the leak was repaired. Basically I would have made sure the cats were bad before just replacing them.
https://www.fixdapp.com/blog/p0420-code/
https://www.fixdapp.com/blog/p0420-code/
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Joined: Apr 2007
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From: Richmond, Virginia USA
'12 E550, '10 ML350, '06 E350, '20 GLC300, '21 GLC300
Thanx for the info. Only codes are P0420,P0430 no others. As stated Dealer serviced vehicle and if there were any issues should have found them and informed me. 200k service car checked front to back and scanned by them also NO CODES found. Exhaust system checked and no issues. Only issues they did find were rear coil springs broken $1093.80 to replace. Front and rear alignment $240.29. Front Passenger side axle seal & Front pinion reseal kit $1854.50. Transfer case reseal kit & hardware $1863.33. My indie rechecked and we are under the same conclusion CATS are done. Got over 200k and they usually last 100k... Going to have other issues addressed soon. CATS first....
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From: Connecticut
E350 4MATIC 2011 W212/S550 4MATIC 2012 W221
replace cats/o2 sensors
[QUO TE=no_mulligan;8411968]With a scan tool, you can look at your short term fuel trim and long term fuel trim. If your O2 sensors are shot, it most certainly will show up here.[/QUOTE]
Thanx for info. After much more info into service records for vehicle 2011 E350 4MATIC and due to the mileage 205006 have decided to change both cats and all O2 sensors.
Thanx for info. After much more info into service records for vehicle 2011 E350 4MATIC and due to the mileage 205006 have decided to change both cats and all O2 sensors.
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Joined: Apr 2007
Posts: 311
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From: Richmond, Virginia USA
'12 E550, '10 ML350, '06 E350, '20 GLC300, '21 GLC300
Are you losing any coolant? Maybe a few ounces after 10,000 miles?
Thread Starter
Junior Member
Joined: Aug 2018
Posts: 24
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From: Connecticut
E350 4MATIC 2011 W212/S550 4MATIC 2012 W221
replace cats
No coolant leaks. Other than rack and pinion seal and transfer case seal as stated by dealer no other concerns.
