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Hi everyone, recently changed the spark plugs on my 2012 CLS 550 and after about 200-300 miles on them, I've noticed a noticeable tick out of the front right driver's side (when looking under the hood towards the front of the car, driver's side on your perceived right looking in the motor bay). I've seen terrifying reports of faulty spark plugs scorching cylinder walls into big repairs, Benz dealership said possible high pressure pump on that side can also tick at times. I'm left wondering what this tick is and have scheduled service to look at it officially but I'm wondering if anyone has experienced this before. I get no sensors or warnings on the car but I'm worried to drive it and damage the cylinders or something like that. Is this video noise obvious to anyone as to what exactly might be the problem? Tomorrow I'm going to uninstall the right side plugs and inspect for burning. I'm also thinking about placing the old spark plugs I have back in just to test if the noise goes away and confirms a possible bad spark plug. Appreciate any thoughts on the matter, thank you! Car only has 52k miles on it. I'm also going to check the oil level tomorrow just to make sure it was topped off properly and not low. Could be a possible clog or lifter tick...but it seems higher on the right side of the motor around the plugs, so really think it's that or some valve of sorts?
I have seen some people say the noise is normal for direct injection but then the left side doesn't exhibit it and I don't recall hearing it prior to changing the spark plugs. Everything was changed with OEM official Mercedes parts bought directly from my local dealership.
Good lord! Ya scorched cylinder is worrying me right about now since changing spark plugs. I'm going to try replacing some of the plugs with my old spark plugs to see if it's a defective spark plug as some have mentioned. If I have a scorched cylinder or failing motor at only 52,000 miles, I'd never own a Mercedes Benz again, I'd be heartbroken.
2013 Weistec 540/715 tuned CLS 550, 2008 E350, and '07 Jaguar S-Type R
Originally Posted by ZestyMozzarella
Good lord! Ya scorched cylinder is worrying me right about now since changing spark plugs. I'm going to try replacing some of the plugs with my old spark plugs to see if it's a defective spark plug as some have mentioned. If I have a scorched cylinder or failing motor at only 52,000 miles, I'd never own a Mercedes Benz again, I'd be heartbroken.
I forgot to ask you how many miles are on your car. 52K miles is nothing for an M278 engine if it's had regular oil changes.
As a '13 CLS550 w/62K miles owner, I pray this is a bad plug, etc. Please keep us updated.
Will do certainly. Car is way too young to be dramatic (I would hope anyway), and it didn't even start until after the spark plug change. I used dielectric grease and the 23nM (16.9 lbs) of torque on each one. I went to Viti this morning and bought three new OEM spark plugs. I'm going to inspect tomorrow to see if anything is off or whether any plugs are burnt, cracked, etc. Hopefully I find the problem and will be working on it all tomorrow morning. I'll report back with my findings, wish me luck ^^
2013 Weistec 540/715 tuned CLS 550, 2008 E350, and '07 Jaguar S-Type R
Originally Posted by ZestyMozzarella
Will do certainly. Car is way too young to be dramatic (I would hope anyway), and it didn't even start until after the spark plug change. I used dielectric grease and the 23nM (16.9 lbs) of torque on each one. I went to Viti this morning and bought three new OEM spark plugs. I'm going to inspect tomorrow to see if anything is off or whether any plugs are burnt, cracked, etc. Hopefully I find the problem and will be working on it all tomorrow morning. I'll report back with my findings, wish me luck ^^
Anxious to hear what you find. I noticed that the MB service schedule calls for plugs replacement at 60K miles - where mine is now. Kind of afraid to do it :P
Hi Digital and forum goers, sorry for the long delayed response, life has been hectic per usual! I did manage to do some research and take a peek at these issues with great success and resolution
So as expected on the driver side, I felt the tick was favoring the front two cylinders. As terrified as I was of a scorched cylinder or damage done to the motor, I decided to extract the front two driver side spark plugs and sure enough, one was fine and the other was scorched! I can only attribute it to a bad or failed spark plug. Anyway, I was hopeful that was the specific problem and replaced it with a new one. Everything is now fine per the video attached, only the sound of belts and motor now! Now other ticks, knocks or sounds coming from the motor or cylinder walls, oil pumps etc. that are suspect. The car only has 52k miles on it so I would have been heartbroken to see something major happen to it let alone off nothing but a bad spark plug. I probably drove on this plug for 200-300 miles before swapping during the course of a week to work back and forth.
Anyway, car is smooth as can be and full power now, operating as it should be. Very glad I found the problem and it was nothing major but just highlights the important of normal motor sound and when you know something is off...probably is and it's good to go digging. I make sure to take care of my baby ^^
I hope this experience and evidence can help guide others in the future that may come across it! Thanks everyone
2013 Weistec 540/715 tuned CLS 550, 2008 E350, and '07 Jaguar S-Type R
Originally Posted by ZestyMozzarella
Hi Digital and forum goers, sorry for the long delayed response, life has been hectic per usual! I did manage to do some research and take a peek at these issues with great success and resolution
So as expected on the driver side, I felt the tick was favoring the front two cylinders. As terrified as I was of a scorched cylinder or damage done to the motor, I decided to extract the front two driver side spark plugs and sure enough, one was fine and the other was scorched! I can only attribute it to a bad or failed spark plug. Anyway, I was hopeful that was the specific problem and replaced it with a new one. Everything is now fine per the video attached, only the sound of belts and motor now! Now other ticks, knocks or sounds coming from the motor or cylinder walls, oil pumps etc. that are suspect. The car only has 52k miles on it so I would have been heartbroken to see something major happen to it let alone off nothing but a bad spark plug. I probably drove on this plug for 200-300 miles before swapping during the course of a week to work back and forth.
Anyway, car is smooth as can be and full power now, operating as it should be. Very glad I found the problem and it was nothing major but just highlights the important of normal motor sound and when you know something is off...probably is and it's good to go digging. I make sure to take care of my baby ^^
I hope this experience and evidence can help guide others in the future that may come across it! Thanks everyone
Congratulations, I can't tell you how glad I am to hear this good news! I have seriously been considering selling mine after reading the accounts of rocking pistons.
That being said, how difficult was it to change plugs? My car has just over 60K miles and MB calls for replacement.
It wasn't too bad and is certainly manageable by the daily DIY'er. This gentleman here seen below has a great video on the M278 motor (CLS550 and others), spark plug change. There are all sorts of tools I needed for the job. If you want when I get home later, I can compile a list of everything I needed to do the work and where the challenges were but it's definitely a job you can do yourself. I think the entire job cost me about $160 or so for plugs and I did end up spending about $330 on tools and what not but I also bought a jack. The tools were an investment where now that I have them, I have them for every job in the future so it was worth it. Tools themselves were probably under $120 but my local Benz dealership (and I swear by OEM and taking care of my baby), because I want to maintain stock condition and what not...they wanted $525 plus tax to do the job, so I still saved money and future spark plugs will only cost me $164 and change now, so I'm good to go.
When I get home, I will compile a few photos and a list of all the tools I needed to do the job and where the tricky parts were, that way you can sort through whether you want to do it yourself and what tools you're missing and need to complete the job ^^
2013 Weistec 540/715 tuned CLS 550, 2008 E350, and '07 Jaguar S-Type R
Originally Posted by ZestyMozzarella
It wasn't too bad and is certainly manageable by the daily DIY'er. This gentleman here seen below has a great video on the M278 motor (CLS550 and others), spark plug change. There are all sorts of tools I needed for the job. If you want when I get home later, I can compile a list of everything I needed to do the work and where the challenges were but it's definitely a job you can do yourself. I think the entire job cost me about $160 or so for plugs and I did end up spending about $330 on tools and what not but I also bought a jack. The tools were an investment where now that I have them, I have them for every job in the future so it was worth it. Tools themselves were probably under $120 but my local Benz dealership (and I swear by OEM and taking care of my baby), because I want to maintain stock condition and what not...they wanted $525 plus tax to do the job, so I still saved money and future spark plugs will only cost me $164 and change now, so I'm good to go.
When I get home, I will compile a few photos and a list of all the tools I needed to do the job and where the tricky parts were, that way you can sort through whether you want to do it yourself and what tools you're missing and need to complete the job ^^
Thank you, but don't go to the trouble - the video gives me an idea of what I need.
I don't need my spark plugs changed, but I still watched the entire video because of that guy's editing skills and videography. It's like ASMR, but I get to learn how to change my spark plugs at the same time.
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