Cylinder 5 misfire
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Junior Member
Joined: Nov 2014
Posts: 71
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2013 GL450
Cylinder 5 misfire
I posted this same story in a reply to another cylinder 5 misfire thread... thought might as well make a new thread instead of hijacking the other thread. Please don't mind me posting the same story/question twice...
My 2013 x166 is at about 100k miles. About 1-2 years ago it started to develop oil consumption and coolant consumption that my mechanics can't really track down. But it's not too severe so I just occasionally top up and live with it.
I have been driving in cold temp (~0F) a lot this winter for our weekly skiing, about a month ago CEL came on, code read cylinder 5 misfirings, although driving was completely fine the car felt normal. The CEL was persistent and didn't go away from restarting the car. I brought it to my mechanic he suggested changing spark plugs first because it has never been changed. CEL didn't come back for a month.
Last week on a cold day (< 0F), a few minutes into driving CEL came up, and this time I actually feel some rhythmic vibration from the engine if I try to give gas, I guess one of the cylinders was not firing/misfiring? I drove gingerly for about 10 miles to get to where we needed to be, then restarted the car, upon restart, there was no CEL and the car was driving fine again... A week passed so far CEL hasn't come back. I didn't have my OBDII scanner with me when the CEL came up so I don't know what code it was.
The episode of feeling that engine vibration was somewhat disconcerting, the last thing I want would be the whole family got stranded on our weekly long drive up to the ski mountain. Any suggestion on what should I do in the meantime, other than waiting for the CEL to come up again?
My 2013 x166 is at about 100k miles. About 1-2 years ago it started to develop oil consumption and coolant consumption that my mechanics can't really track down. But it's not too severe so I just occasionally top up and live with it.
I have been driving in cold temp (~0F) a lot this winter for our weekly skiing, about a month ago CEL came on, code read cylinder 5 misfirings, although driving was completely fine the car felt normal. The CEL was persistent and didn't go away from restarting the car. I brought it to my mechanic he suggested changing spark plugs first because it has never been changed. CEL didn't come back for a month.
Last week on a cold day (< 0F), a few minutes into driving CEL came up, and this time I actually feel some rhythmic vibration from the engine if I try to give gas, I guess one of the cylinders was not firing/misfiring? I drove gingerly for about 10 miles to get to where we needed to be, then restarted the car, upon restart, there was no CEL and the car was driving fine again... A week passed so far CEL hasn't come back. I didn't have my OBDII scanner with me when the CEL came up so I don't know what code it was.
The episode of feeling that engine vibration was somewhat disconcerting, the last thing I want would be the whole family got stranded on our weekly long drive up to the ski mountain. Any suggestion on what should I do in the meantime, other than waiting for the CEL to come up again?
Out Of Control!!
Joined: Sep 2018
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From: unbegrenzt
2017 GLE350 4MATIC
Pull the plugs and inspect them, use a borescope to look down the cylinders and check compression on all cylinders. Or drive it until the inevitable happens.
In the mean time, start weighing the options for major repair expense or new vehicle.
In the mean time, start weighing the options for major repair expense or new vehicle.
Super Member
Joined: Jul 2019
Posts: 733
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From: New Orleans
2014 GL450, 1992 W140 300SD, 1993 W140 300SE, 1987 E30 Convertible
Could be one of your ignition coils or fuel injectors acting up. Cure is simple restart and replacement - if you will figure out which one is not properly functioning.
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2013 GL450
Cars are still expensive and somewhat limited supply now, I'm looking at CPO gls, ~50k of 2017/2018 x166, or ~70k+ 2020 x167... I feel a bit silly to get out of one x166 just to get into another newer x166, while the x167 seems expensive not too much cheaper than MSRPs. So I want to hold on to the car maybe a little longer (1 or 2 years?) if possible but it's hard to get a sense of if some major repair is looming unless I start sinking money into doing checks/diagnoses (like borescope, compression test, etc)...
Out Of Control!!
Joined: Sep 2018
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From: unbegrenzt
2017 GLE350 4MATIC
I know man... it has been on my mind - given that the car has been consuming some oil and coolant, now these CELs...
Cars are still expensive and somewhat limited supply now, I'm looking at CPO gls, ~50k of 2017/2018 x166, or ~70k+ 2020 x167... I feel a bit silly to get out of one x166 just to get into another newer x166, while the x167 seems expensive not too much cheaper than MSRPs. So I want to hold on to the car maybe a little longer (1 or 2 years?) if possible but it's hard to get a sense of if some major repair is looming unless I start sinking money into doing checks/diagnoses (like borescope, compression test, etc)...
Cars are still expensive and somewhat limited supply now, I'm looking at CPO gls, ~50k of 2017/2018 x166, or ~70k+ 2020 x167... I feel a bit silly to get out of one x166 just to get into another newer x166, while the x167 seems expensive not too much cheaper than MSRPs. So I want to hold on to the car maybe a little longer (1 or 2 years?) if possible but it's hard to get a sense of if some major repair is looming unless I start sinking money into doing checks/diagnoses (like borescope, compression test, etc)...
The 2017-2019 X166 GLS450 is probably the best MB available preowned now. Reliable engine and chassis, with the GLS luxury goodies.
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2013 GL450
I was under the impression that the cylinder 5 problem is common in the m278 engine, so I thought I should try to avoid the newer x166 given it's using the same engine...
Last edited by byroncheung; Feb 3, 2022 at 02:03 PM.
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From: Gresham, OR
GL450
The M278 V8 is only used in de-tuned form in the 2013 and 2014 GL450 for the X166, after 2015 the X166 GL450 and GLS450 went to a M276 V6 (at least in the US). The GL550 and GLS550 stayed with the M278 to 2019. (The Wikipedia page for the X166 talks about a GLS400, GL500, and GLS500, I think those are the European model names) If you really want to stay in an x166 but don't want a M278, you can get a 2015+ GL450/GLS450, get a diesel engine GL350, or throw caution and money to the wind and get an AMG GL63/GLS63.
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Thread Starter
Junior Member
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2013 GL450
The M278 V8 is only used in de-tuned form in the 2013 and 2014 GL450 for the X166, after 2015 the X166 GL450 and GLS450 went to a M276 V6 (at least in the US). The GL550 and GLS550 stayed with the M278 to 2019. (The Wikipedia page for the X166 talks about a GLS400, GL500, and GLS500, I think those are the European model names) If you really want to stay in an x166 but don't want a M278, you can get a 2015+ GL450/GLS450, get a diesel engine GL350, or throw caution and money to the wind and get an AMG GL63/GLS63.
my main question will be is the m276 more robust than the m278?
Last edited by byroncheung; Feb 3, 2022 at 04:10 PM.
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Out Of Control!!
Joined: Sep 2018
Posts: 14,695
Likes: 4,586
From: unbegrenzt
2017 GLE350 4MATIC
Yes, the 2017-2019 GLS450 using the well regarded and reliable M276 3.0 TT V6.
Any MB vehicle with the EQ Boost 48V hybrid system is to be strongly avoided, this includes the current model X167 GLS.
Any MB vehicle with the EQ Boost 48V hybrid system is to be strongly avoided, this includes the current model X167 GLS.
Thread Starter
Junior Member
Joined: Nov 2014
Posts: 71
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2013 GL450
Out Of Control!!
Joined: Sep 2018
Posts: 14,695
Likes: 4,586
From: unbegrenzt
2017 GLE350 4MATIC
@chassis so what’s bad about the hybrid system? Reliability?
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From: Alberta, Canada
GL350, C43 Wagon, 911 C2S
I had this happen on my 2006 V8 Touareg about 3 years into owenerrship, the dealer replaced the coils and plugs and the issue didn't resurface for the next 14 years. I know it's a different car/engine etc.
Thread Starter
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2013 GL450
no smoke, I don’t think it is giving more smoke compared to back in the days it wasn’t consuming between maintenance cycles…
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From: New Orleans
2014 GL450, 1992 W140 300SD, 1993 W140 300SE, 1987 E30 Convertible
Could be just a burned exhaust valve which is more common for cyl 5.
Reason is too short exhaust manifold, constant overheating because of back pressure.
Reason is too short exhaust manifold, constant overheating because of back pressure.
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2013 GL450
