In trouble, need guidance
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‘12 S550
In trouble, need guidance
Hi All, I am the owner of a 2012 S550 4Matic, and the check engine light has been coming on. There are several cylinder misfires going on as well as an incorrect intake camshaft value. I took it to a couple of Indy's and was quoted $13K by one of them, and $10K by another (both of whom are reluctant about even working on it). I'm being told that the timing chain has gotten extended and would need replacing. I feel like getting another M278 engine and having it installed would save me a sizeable amount.
Last edited by sHocKR3P4IR; Aug 29, 2022 at 05:56 PM.
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2017 GLE350 4MATIC
M278 isn't aging well. Valve guides, cylinder scoring, oil in the harness, turbo oil lines. I wouldn't buy an M278. On paper it's a great engine. Apparently also when it isn't broken. But it breaks.
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‘12 S550
Yeah, seems like it. I’ve noticed that M273s are going for way cheaper than the M278s…how much of a nightmare would I encounter in putting an M273 (from either a 2010 or 2011) into a 2012 S550 which came from the factory with an M278? Potential, more cost-effective solution? Or am I missing something.
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04 E55 AMG (totaled), 07 S550 4Matic, 14 E63S
In OP's defense, he has a very early one....
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2017 GLE350 4MATIC
Yeah, seems like it. I’ve noticed that M273s are going for way cheaper than the M278s…how much of a nightmare would I encounter in putting an M273 (from either a 2010 or 2011) into a 2012 S550 which came from the factory with an M278? Potential, more cost-effective solution? Or am I missing something.
If you must have a W221 I would go with the M273 or V12. The M272 V6, if it exists in your market, is known for balancer assembly problems.
Or look at either a 6 or 12 cylinder W222. M276 3.0TT W222 would be a reliable powertrain, the rest of the vehicle I can't comment on (air suspension, seats, entertainment electronics). V12 W222 were not built in high volume and are probably expensive.
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2010 E550, 273 Engine: 2012 S550, 278 Engine
Hi All, I am the owner of a 2012 S550 4Matic, and the check engine light has been coming on and won't go away. There are several cylinder misfires going on as well as an incorrect intake camshaft value. I took it to a couple of Indy's and was quoted $13K by one of them, and $10K by another (both of whom are reluctant about even working on it). I'm being told that the timing chain has gotten extended and would need replacing. I feel like getting another M278 engine and having it installed would save me a sizeable amount--though I've no idea how to go about that or who can help. Any tips, advice, or someone you can point me towards? I'm based in Chicago if that helps at all. I was really hoping to drive the car for another 5-7 years. Thanks.
Timing issues (misfire) typically result from sensor issues and if not replaced yet it is time to do that. These sensors are the Crank Shaft Position sensor and the four Cam Shaft Position sensors. Crank sensor cost about $160 if I remember correctly.
Crank sensor replacement is a little bit of a hard job to do if you want to tackle it your self but doable. I did it.
The Cam sensors are super easy to replace. They cost $84 a piece + tax from the dealer. These sensors are on the top and side of the cylinder heads in front of the engine and fastened with one screw each. New sensors made my engine run much smoother.
You can buy just one Cam sensor and replace one of the sensors to see if it helps. If not move it to the next one and so on. Sensors are all the same. If Cam sensors don’t help then replace the Crank sensor.
Last edited by Arrie; Aug 27, 2022 at 10:51 AM.
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‘12 S550
Lets keep it simple.
Timing issues (misfire) typically result from sensor issues and if not replaced yet it is time to do that. These sensors are the Crank Shaft Position sensor and the four Cam Shaft Position sensors. Crank sensor cost about $160 if I remember correctly.
Crank sensor replacement is a little bit of a hard job to do if you want to tackle it your self but doable. I did it.
The Cam sensors are super easy to replace. They cost $84 a piece + tax from the dealer. These sensors are on the top and side of the cylinder heads in front of the engine and fastened with one screw each. New sensors made my engine run much smoother.
You can buy just one Cam sensor and replace one of the sensors to see if it helps. If not move it to the next one and so on. Sensors are all the same. If Cam sensors don’t help then replace the Crank sensor.
Timing issues (misfire) typically result from sensor issues and if not replaced yet it is time to do that. These sensors are the Crank Shaft Position sensor and the four Cam Shaft Position sensors. Crank sensor cost about $160 if I remember correctly.
Crank sensor replacement is a little bit of a hard job to do if you want to tackle it your self but doable. I did it.
The Cam sensors are super easy to replace. They cost $84 a piece + tax from the dealer. These sensors are on the top and side of the cylinder heads in front of the engine and fastened with one screw each. New sensors made my engine run much smoother.
You can buy just one Cam sensor and replace one of the sensors to see if it helps. If not move it to the next one and so on. Sensors are all the same. If Cam sensors don’t help then replace the Crank sensor.
If replacing the cam sensors and crank sensor doesn't fix it, what is the next step you would take?
Thanks.
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This place is a joke.
I doubt the sensors are bad, unless the harness is oil soaked. This may be a stretched timing chain, or worse. Replacing all the chains is an engine out and apart nightmare of a job with many things that can go wrong. I'm not surprised nobody wants to touch it. I wouldn't. These are fragile engines not really meant to be taken apart once they leave the assembly line. It could also be an issue with a camshaft pulse wheel or adjuster.
Last edited by E55Greasemonkey; Aug 27, 2022 at 12:23 PM.
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From: unbegrenzt
2017 GLE350 4MATIC
Thanks, I'll start off with that. Would these work? Mercedes Camshaft Position Sensor - Genuine Mercedes 2769051000 | FCP Euro
If replacing the cam sensors and crank sensor doesn't fix it, what is the next step you would take?
Thanks.
If replacing the cam sensors and crank sensor doesn't fix it, what is the next step you would take?
Thanks.
If ultimately you decide to purchase sensors or magnets, buy them from the dealer or mbparts.mbusa.com. Always OEM from the dealer for electrical parts, especially sensors.
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‘12 S550
Agree with @E55Greasemonkey . The problem might not be the sensors or magnets.
If ultimately you decide to purchase sensors or magnets, buy them from the dealer or mbparts.mbusa.com. Always OEM from the dealer for electrical parts, especially sensors.
If ultimately you decide to purchase sensors or magnets, buy them from the dealer or mbparts.mbusa.com. Always OEM from the dealer for electrical parts, especially sensors.
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the diagnosis shared here is insufficent
misfire - caused by ? coil packs drop dead on any modern car or bike - might be this if lucky $40 each
a modern merc with a stretched cam chain - normal - fit a new one $400
EML could be either cam timing or coil packs, and indeed a crank sensor which is another merc trick
reading between the lines - designed to die engineering - lease your next car - its how they make 'em now
misfire - caused by ? coil packs drop dead on any modern car or bike - might be this if lucky $40 each
a modern merc with a stretched cam chain - normal - fit a new one $400
EML could be either cam timing or coil packs, and indeed a crank sensor which is another merc trick
reading between the lines - designed to die engineering - lease your next car - its how they make 'em now
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‘12 S550
the diagnosis shared here is insufficent
misfire - caused by ? coil packs drop dead on any modern car or bike - might be this if lucky $40 each
a modern merc with a stretched cam chain - normal - fit a new one $400
EML could be either cam timing or coil packs, and indeed a crank sensor which is another merc trick
reading between the lines - designed to die engineering - lease your next car - its how they make 'em now
misfire - caused by ? coil packs drop dead on any modern car or bike - might be this if lucky $40 each
a modern merc with a stretched cam chain - normal - fit a new one $400
EML could be either cam timing or coil packs, and indeed a crank sensor which is another merc trick
reading between the lines - designed to die engineering - lease your next car - its how they make 'em now
So this is the info I’ve received in terms of the diagnosis. That and one of the indy’s says he can hear the timing chain slapping around inside.
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S500
yes but that is just drivel - there will be a code explaining what the misfire is caused by - an old world compression test would be more useful - and as others said, the cam timing can be nothing on a modern merc - it will have said exactly how far out it was
based on that I not be going to them - it appears they haven't even got a fake copy of xentry so they might just be robbing you
based on that I not be going to them - it appears they haven't even got a fake copy of xentry so they might just be robbing you
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Yes leaking is a distraction and not the cause.
@sHocKR3P4IR you need to find the root cause. Possibly:
- stretched chain
- failed tensioners
- slipped cam position plate or ring
- failed position sensor
- failed magnet
- or multiple of the above
More diagnosis by you or your shop is needed. No amount of reposting the service invoices will solve this over the internet.
@sHocKR3P4IR you need to find the root cause. Possibly:
- stretched chain
- failed tensioners
- slipped cam position plate or ring
- failed position sensor
- failed magnet
- or multiple of the above
More diagnosis by you or your shop is needed. No amount of reposting the service invoices will solve this over the internet.
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‘12 S550
Yes leaking is a distraction and not the cause.
@sHocKR3P4IR you need to find the root cause. Possibly:
- stretched chain
- failed tensioners
- slipped cam position plate or ring
- failed position sensor
- failed magnet
- or multiple of the above
More diagnosis by you or your shop is needed. No amount of reposting the service invoices will solve this over the internet.
@sHocKR3P4IR you need to find the root cause. Possibly:
- stretched chain
- failed tensioners
- slipped cam position plate or ring
- failed position sensor
- failed magnet
- or multiple of the above
More diagnosis by you or your shop is needed. No amount of reposting the service invoices will solve this over the internet.
Thread Starter
Junior Member
Joined: Aug 2022
Posts: 26
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‘12 S550
the diagnosis shared here is insufficent
misfire - caused by ? coil packs drop dead on any modern car or bike - might be this if lucky $40 each
a modern merc with a stretched cam chain - normal - fit a new one $400
EML could be either cam timing or coil packs, and indeed a crank sensor which is another merc trick
reading between the lines - designed to die engineering - lease your next car - its how they make 'em now
misfire - caused by ? coil packs drop dead on any modern car or bike - might be this if lucky $40 each
a modern merc with a stretched cam chain - normal - fit a new one $400
EML could be either cam timing or coil packs, and indeed a crank sensor which is another merc trick
reading between the lines - designed to die engineering - lease your next car - its how they make 'em now
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2007 S600, 2007 Chrysler 300 SRT8, 2000 C5 Corvette, 2017 Mustang GT, 2023 300C, and a 2019 Lincoln
Just read you were in Chicago. I was always told in Chicago, if you had a bad engine; the car could get stolen and burned. Of course, that never happens here in DC.
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From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
I know it is a stretched chain, that was the conclusion reached by the indy after further diagnosis. Though it would be worth replacing the sensors and tensioners since those are simpler fixes to trial. The thing i’m trying to figure out is if swapping out the M278 could be the better way to go than to try replacing the chain, and if I can find anyone to help with that.
What if the chain rattle is caused by the chain tensioners that do not hold oil as the check valves were not installed?
Oil leak on timing cover, or is it the oil leaking thru the cam position sensor? In my case I got the Check Engine Light. Quick code reading with the scanner reported issue with the cam position sensor. When I removed the small engine cover around the oil filler I could see the whole engine under that cover was covered with oil and I could see the leak was thru the cam sensor that is located on top of the engine. The wiring harness was full of oil and if I was you, I would buy one cam sensor from the dealer and replace the sensors one-by-one to see if one of them is faulty. It is very unlikely that more than one sensor decides to go bad at the same time. You might also be able to identify that the timing cover leak they talk about is actually oil leaking thru the cam sensor.
Because one of mine went bad to a point that oil leaked thru it, I decided to replace them all. I have done 3 of them as every dealer I go to only has one in stock and they have to order so I get these one at the time. I drive a lot for my work, so I buy these in different cities. I have one to go and I can say my engine runs a lot smoother after replacing three of them. I will still replace the last fourth one too.
But as it seems you want to replace the engine so go ahead. It just is that if it is a used engine, you might be with the same problem with these sensors.
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‘12 S550
And how did your indy mechanic exactly diagnose that it is a stretched chain? This is something you can't diagnose without opening the engine front.
What if the chain rattle is caused by the chain tensioners that do not hold oil as the check valves were not installed?
Oil leak on timing cover, or is it the oil leaking thru the cam position sensor? In my case I got the Check Engine Light. Quick code reading with the scanner reported issue with the cam position sensor. When I removed the small engine cover around the oil filler I could see the whole engine under that cover was covered with oil and I could see the leak was thru the cam sensor that is located on top of the engine. The wiring harness was full of oil and if I was you, I would buy one cam sensor from the dealer and replace the sensors one-by-one to see if one of them is faulty. It is very unlikely that more than one sensor decides to go bad at the same time. You might also be able to identify that the timing cover leak they talk about is actually oil leaking thru the cam sensor.
Because one of mine went bad to a point that oil leaked thru it, I decided to replace them all. I have done 3 of them as every dealer I go to only has one in stock and they have to order so I get these one at the time. I drive a lot for my work, so I buy these in different cities. I have one to go and I can say my engine runs a lot smoother after replacing three of them. I will still replace the last fourth one too.
But as it seems you want to replace the engine so go ahead. It just is that if it is a used engine, you might be with the same problem with these sensors.
What if the chain rattle is caused by the chain tensioners that do not hold oil as the check valves were not installed?
Oil leak on timing cover, or is it the oil leaking thru the cam position sensor? In my case I got the Check Engine Light. Quick code reading with the scanner reported issue with the cam position sensor. When I removed the small engine cover around the oil filler I could see the whole engine under that cover was covered with oil and I could see the leak was thru the cam sensor that is located on top of the engine. The wiring harness was full of oil and if I was you, I would buy one cam sensor from the dealer and replace the sensors one-by-one to see if one of them is faulty. It is very unlikely that more than one sensor decides to go bad at the same time. You might also be able to identify that the timing cover leak they talk about is actually oil leaking thru the cam sensor.
Because one of mine went bad to a point that oil leaked thru it, I decided to replace them all. I have done 3 of them as every dealer I go to only has one in stock and they have to order so I get these one at the time. I drive a lot for my work, so I buy these in different cities. I have one to go and I can say my engine runs a lot smoother after replacing three of them. I will still replace the last fourth one too.
But as it seems you want to replace the engine so go ahead. It just is that if it is a used engine, you might be with the same problem with these sensors.
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S500
my local merc indy does cam chains everyday - I don't know this engine - but the standard is to pull the new chain around using the old one - so there isn't much to do - skilled and of course must be done carefully - but vastly cheaper than a replacement engine
that's the whole point of the stop start rip off - one jet flying out of LAX puts out 10 times the pollution saved by every car that's ever turned itself off at the lights - but it destroys the weaker cam chains they now fit - to push you in to leasing that next car
I used to swap out the old jag XK engine in 9 hours on a Series 3 - talking to mates that run a jag indie they were swapping out the V8 engine on an modern F type the other day - two of them on it, and there was shed loads more detritus to swap over, I asked how long it would take - 40hours is the book time, was the reply !!!!
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From: unbegrenzt
2017 GLE350 4MATIC
The vehicle has an M278 with codes and leaks. @sHocKR3P4IR please explain how you or your mechanic have concluded the chain is stretched.
Ignore leaks, they are not the source of codes. Leaks on M27* engines are from poor factory quality control, do not cause codes, and can be repaired by the dealer.
Codes are caused by the ECU thinking something is wrong.
- Focus on the easy things first: cam position sensors and cam solenoids allowing oil to enter the harness. This is the least expensive and most likely failure - 2012 was the first year for M278 in W221 and therefore has the most time on the road/in use. Cam position sensors have had a multitude of part number changes which is a red flag that MB knew they had a problem and were flailing around trying to find a solution.
- After oil in harness has been affirmatively ruled out, move to mechanical parts: chain, tensioner and cam plates.
Ignore leaks, they are not the source of codes. Leaks on M27* engines are from poor factory quality control, do not cause codes, and can be repaired by the dealer.
Codes are caused by the ECU thinking something is wrong.
- Focus on the easy things first: cam position sensors and cam solenoids allowing oil to enter the harness. This is the least expensive and most likely failure - 2012 was the first year for M278 in W221 and therefore has the most time on the road/in use. Cam position sensors have had a multitude of part number changes which is a red flag that MB knew they had a problem and were flailing around trying to find a solution.
- After oil in harness has been affirmatively ruled out, move to mechanical parts: chain, tensioner and cam plates.
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S500
engine number?
https://mbworld.org/forums/attachmen...version_10.pdf
Engine 278:
Up to engine 2789xx 30 103675, install chain tensioners and check valves.
From engine 2789xx 30 103676 to engine 2789xx 30 191843, install chain tensioners only.
If the noise problem is not rectified after installing the new chain tensioners and check valves, or if the engine number
of the affected engine is higher than the corresponding engine listed under Validity, report the complaint via the PTSS
system with the current quick test results
https://mbworld.org/forums/attachmen...version_10.pdf
Engine 278:
Up to engine 2789xx 30 103675, install chain tensioners and check valves.
From engine 2789xx 30 103676 to engine 2789xx 30 191843, install chain tensioners only.
If the noise problem is not rectified after installing the new chain tensioners and check valves, or if the engine number
of the affected engine is higher than the corresponding engine listed under Validity, report the complaint via the PTSS
system with the current quick test results
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From: Iowa
2008 CL550, 2022 EQB 300, 2023 EQS 450 4Matic
I've got an M273 engine with fault code P0025 (continuous camshaft adjustment left incorrect position of the exhaust camshaft). Anyone know what this code has in store for me? The car runs fine--just picked it up on a regular quick scan with my Foxwell scanner.
