M-Class (W164) Produced 2006-2011: ML280CDI, ML320CDI, ML420CDI, ML350, ML500, ML550

Glow plug CEL P0672

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Mar 25, 2012 | 06:01 PM
  #1  
mbhouston's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2011
Posts: 23
Likes: 0
From: Texas
2008 ml320 CDi
Glow plug CEL P0672

Hi,
I have 2008 320 cdi, the glow plug lamp on occasion takes 30 - 40 seconds to go off. Not regular. The CEL came on, i tested this at Autozone and it gave a code P0672....indicates the number 2 cylinder glow plug may be faulty. By the time i received a new one ordered from the dealer, the CEL went off and the GP light turned of as usual..1-2 secs. I went ahead and installed the number 2 cylinder GP. Everything was fine for two weeks. A few days ago, the GP light took 30-40 secs to go off...very sporadic. Yesterday the CEL came on and same code P0672. I have a new GP, could the module be going out? Now GP light goes out as normal but CEL is on.

Any clues?
Thanks
MB
Reply
Old Mar 25, 2012 | 09:07 PM
  #2  
GSD's Avatar
GSD
Junior Member
 
Joined: Jul 2011
Posts: 37
Likes: 0
From: Ontario, Canada
2007 ML320CDI 2004 Jetta TDI
spray deoxit in the harness and try that first.
Reply
Old Mar 25, 2012 | 11:53 PM
  #3  
mbhouston's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2011
Posts: 23
Likes: 0
From: Texas
2008 ml320 CDi
GSD, thanks for the reply. Can you please be more specific, where exactly should i spray, in the connector that plugs over the glow plug? Where do i get deoxit from, any brand name? I am assuming this is a deoxidizer?

Thanks for the help.
MBP
Reply
Old Mar 26, 2012 | 08:15 AM
  #4  
C43AMG's Avatar
MBWorld Fanatic!
Veteran: Army
20 Year Member
Liked
Loved
 
Joined: Feb 2005
Posts: 5,761
Likes: 4
From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
Glow plug relay ?
Reply
Old Mar 26, 2012 | 07:01 PM
  #5  
GSD's Avatar
GSD
Junior Member
 
Joined: Jul 2011
Posts: 37
Likes: 0
From: Ontario, Canada
2007 ML320CDI 2004 Jetta TDI
Originally Posted by mbhouston
GSD, thanks for the reply. Can you please be more specific, where exactly should i spray, in the connector that plugs over the glow plug? Where do i get deoxit from, any brand name? I am assuming this is a deoxidizer?

Thanks for the help.
MBP
Spray the deoxit in the harness where it connects to the Glow Plug.

Deoxit is normally available at TV, Hifi repair shops and removes oxidization. You can also check the resistance of the glow plugs with a ammeter/volt meter too.

Take a look at this thread on a TDI
Reply
Old May 12, 2012 | 02:58 PM
  #6  
mbhouston's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2011
Posts: 23
Likes: 0
From: Texas
2008 ml320 CDi
Hi,
CEL reset it self. It was fine for a while. Glow plug light was taking 40 secs on occasion to go off for a few days. CEL came on again. I checked the code, it is the same code P0672. Odd thing, when I turn the key on, glow plug light goes of as usual, once the car starts, it comes on for 40 sec plus, and goes off.
I used deoxit on all the connectors.

Could the timer be going out? Thanks
MBP
Reply
Old May 12, 2012 | 10:27 PM
  #7  
C43AMG's Avatar
MBWorld Fanatic!
Veteran: Army
20 Year Member
Liked
Loved
 
Joined: Feb 2005
Posts: 5,761
Likes: 4
From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
Glow plug relay ?
Reply
Old May 13, 2012 | 09:03 AM
  #8  
mbhouston's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2011
Posts: 23
Likes: 0
From: Texas
2008 ml320 CDi
Is the relay a common problem?

Thanks
Reply
MB World Stories

The Best of Mercedes & AMG

story-0

New Mercedes-AMG SUVs Arrive With NEW V8 Engine: 12 Things You Need to Know

 Verdad Gallardo
story-1

8 Oddball Mercedes Ideas That Actually Made it to Production

 Verdad Gallardo
story-2

Dubai Tuner Gives the Mercedes G-Class An Entirely New Look

 Verdad Gallardo
story-3

Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish

 
story-4

7 Craziest Things AMG Gas Ever Built

 Verdad Gallardo
story-5

New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know

 Verdad Gallardo
story-6

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

 Verdad Gallardo
story-7

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

 Verdad Gallardo
story-8

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

 Verdad Gallardo
story-9

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

 Verdad Gallardo
Old May 13, 2012 | 03:47 PM
  #9  
GSD's Avatar
GSD
Junior Member
 
Joined: Jul 2011
Posts: 37
Likes: 0
From: Ontario, Canada
2007 ML320CDI 2004 Jetta TDI
Did you measure the resistance on each plug?
Reply
Old May 14, 2012 | 10:18 PM
  #10  
mbhouston's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2011
Posts: 23
Likes: 0
From: Texas
2008 ml320 CDi
what should the resistance be? can I measure while the plug is still in?
Thanks
Reply
Old May 28, 2012 | 06:31 PM
  #11  
C43AMG's Avatar
MBWorld Fanatic!
Veteran: Army
20 Year Member
Liked
Loved
 
Joined: Feb 2005
Posts: 5,761
Likes: 4
From: North Carolina
98 Black C43 , 12’ ML 350 Blutec
Originally Posted by mbhouston
Is the relay a common problem?

Thanks
Don't know if it's "common" ....it cost me $600.00 to have it fixed
Reply
Old May 28, 2012 | 07:47 PM
  #12  
mbhouston's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2011
Posts: 23
Likes: 0
From: Texas
2008 ml320 CDi
Thanks for the reply. I can buy from the dealership for $130...will take 20 minutes to install. Just want to have a little insight on similar experiences and the outcome. I will buy from this dealership..online.
http://www.genuinemercedesparts.com/...&siteid=215306

Regards
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 03:03 AM.

story-0
New Mercedes-AMG SUVs Arrive With NEW V8 Engine: 12 Things You Need to Know

Slideshow: Mercedes-AMG's updated GLE 63 S and GLS 63 bring a new-generation V8, subtle design revisions, and familiar supercar-rivaling performance figures.

By Verdad Gallardo | 2026-06-17 12:52:51


VIEW MORE
story-1
8 Oddball Mercedes Ideas That Actually Made it to Production

Slideshow: Mercedes has never been afraid to experiment, and some of its strangest ideas turned out to be surprisingly successful.

By Verdad Gallardo | 2026-06-10 17:43:40


VIEW MORE
story-2
Dubai Tuner Gives the Mercedes G-Class An Entirely New Look

Sideshow: A Middle Eastern tuner has transformed the Mercedes-AMG G 63 into an open-top special, replacing nearly every exterior panel in the process.

By Verdad Gallardo | 2026-06-10 15:29:50


VIEW MORE
story-3
Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish

Slideshow: Six gift ideas your AMG loving dad or grad will cherish.

By | 2026-06-03 17:26:18


VIEW MORE
story-4
7 Craziest Things AMG Gas Ever Built

Slideshow: Sometimes AMG builds fast sedans. Other times, it builds twin-turbo V12 land missiles and six-wheeled off-road monsters.

By Verdad Gallardo | 2026-05-26 17:59:58


VIEW MORE
story-5
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know

Slideshow: Mercedes-AMG's new electric GT 4-Door Coupe trades combustion for software, synthetic noise, and more than 1,100 horsepower.

By Verdad Gallardo | 2026-05-20 20:08:15


VIEW MORE
story-6
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-7
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-8
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-9
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE